This also includes proper test strings.

This moves the documentation out of the constructor, and into the class
definition.

This allows easy creation of unfiltered copies of filtered graphs.

Now if a GraphView object is deleted, any property map created for it
reverts its ownership to the base Graph object. This eliminates the
problem of property maps created with transient GraphView objects.

Now GraphView.base points to the underlying, unfiltered, base graph,
even if "g" is another GraphView instance.

This makes sphinx's autodoc slightly happier.

This implements a GraphView class which allows for convenient,
independent filtering graphs.

Added more DOI links to references, and other cosmetic changes.

The arrays returned by PropertyMap.get_array() are now PropertyArray
instances, which keep track of the PropertyMap data, and are able to
detect when it changes, and raise a ValueError exception. As such, it
becomes impossible to read or write to non-allocated memory if an array
becomes invalid.

This completes all the documentation up to this point.

These functions group several scalar properties into one vector
properties, and ungroup a vector property into several scalar
properties.

No longer only thrown GraphError upon any error, but instead throw
specific exceptions which are more meaninful and are mapped to standard
python exceptions, such as IOError, ValueError and RuntimeError.

This prints useful library information.

Import numpy and scipy before everything to avoid weird segmentation
faults depending on the order things are imported.

This modified several docstrings and introduces a quick-start guide.

Add support for v.{out|in}_neighbours(), for direct iteration over the
neighbours, as well as v.all_edges() and v.all_neighbours(). This also
properly exports the Vertex and Edge classes, with docstrings.

Avoids having to do

    g = Graph()
    g.load("foo")

each time. Now one can do simply,

    g = load_graph("foo")

Fantastic.

Now graphml files properly contain all the supported value types, which
are all perfectly preserved when read (floating point data is now saved
in hexadecimal format). Several other improvements were made, such as
the ability to read and write to python file-like objects.

It is also now possible to have arbitrary python object properties, and
store them persistently (which is done internally with the pickling
interface).

vector<bool> was totally abolished, since its implementation is quite
broken. See: http://www.gotw.ca/publications/N1211.pdf and
http://www.gotw.ca/publications/N1185.pdf Now a uint8_t (aka. char) is
used in graph properties instead of a bool.

Graph types can now be fully pickled (this may not be feasible
memory-wise if the graph is too large, since the whole XML
representation is dumped to a string before it is saved on disc).

This commit splits libraph_tool into different libraries:
 
   - libgraph_tool_core
   - libgraph_tool_clustering (*)
   - libgraph_tool_community (*)
   - libgraph_tool_correlations (*)
   - libgraph_tool_distance (*)
   - libgraph_tool_generation (*)
   - libgraph_tool_layout (*)
   - libgraph_tool_misc (*)
   - libgraph_tool_stats (*)

It also adds the python sub-module 'test', which provides extensive unit
testing of the core functionality. The core library is fully functional
and all test pass successfully.

(*) -> module needs to be ported to new refactoring, and does not yet build

Everything was moved into the graph_tool directory, which should have,
after installation, the following structure:

graph_tool/                          Top-level package
      __init__.py                    Initialize the graph_tool package
      libgraph_tool.so               libgraph_tool submodule
      libgraph_tool.la               libtool file for libgraph_tool
      include/                       C++ include files for dynamically
                                     compiled code

Some visibility voodoo is necessary to ensure that RTTI work properly
across DSO boundaries, which is necessary to properly handle dynamic
property maps and such. Additionally, the action template must have a
different name each time the action code changes, to avoid additional
weirdness.

This also adds some other utility functions/typedefs to make writing
"inline" c++ code easier.

add_edge_property() should return a edge property not a vertex_property

It is now possible to run arbitrary "inline" C++ code from python, using
scipy.weave, as such:

        g = graph_tool.Graph()
        g.load("foo.xml")
        value = 2.0
        g.run_action('cout << num_vertices(g) << " " << value << endl;',
                     ["value"]);

The code gets compiled the first time, and is reused after that. Python
local and global variables can be passed to C++, as shown above, by
specifying a list of passed variables as the second argument.

The graph object passed to the edit function is now a instance of the
Graph class which wraps GraphInterface, not a GraphInterface instance.

Graphs can now be loaded "lazily" with the lazy_load() function, which
works just like load(), but doesn't actually load the graph, which is
delayed until the graph is accessed for the first time, e.g.

    import graph_tool

    g = graph_tool.Graph()
    g.lazy_load("example.xml")

    g.number_of_vertices()  # <- the graph is only loaded here

Property maps can now be obtained as such:

         weight = g.edge_properties['weight']
         print weight[v] # v is a Vertex object
         weight[v] = 2.0
         # and so on...

The list of properties is obtained from g.vertex_properties,
g.edge_properties and g.graph_properties, which can be read as
dictionaries. The last can be set also, as such:

         g.graph_properties = {foo:"bar", baz:42}

Functions to add and remove vertices or adges were also added
(add_{vertex|edge}, remove_{vertex|edgge}).

Vertex and Edge types can also now be printed for convenience, as such:

       for v in g.vertices():
           print v
       for e in g.edges():
           print e

which results, for example, in:
0
1
2
3
4
5
6
(0,1)
(1,2)
(2,6)
(3,4)
(4,5)
(4,2)
(5,6)
(6,1)

(this also adds the forgotten graph_tool.py file, which was previously
on .gitignore)