Python: fixed an issue with Unicode attribute names in Python 2.x; closes #549
R: added more test cases for LAD.
Fixed two invalid reads in LAD, by Tamas.
Merge branch 'develop' of github.com:igraph/igraph into develop
R: fixed a bug when many graphs were created, causing #550.
webpage: added installation instructions for Python
R: fixed two sparse graph.adjacency bugs for graphs with one edge.
R: fixed another sparse get.adjacency but, for empty graphs.
WWW: add TOC for 'Getting started with Python igraph'.
WWW: fix building Python docs, need to build the package first.
fixed a bug that filled the FINALLY stack in igraph_shortest_paths_bellman_ford
R: fixed typo in graph.formula manual page.
R: fixed undirected, weighted, sparse constructor, #554.
R: 'main', 'sub', 'xlab' and 'ylab' are proper graphics parameters now (#555).
Python: added rich comparison and hashing to Vertex and Edge classes
bumped Debian standards version to 3.9.4
Python: Py_hash_t hack is also needed for Python 3.1
R: add vertex names to 'karate' in igraphdata's karate data set.
R: added bug reports field to DESCRIPTION file.
Python: updated Debian package build files