Unit Testing

[greebie]

Provide proper unit testing for function definitions:

• [ ] write_report
• [ ] push
• pushRank // no longer used
• init // no longer used
• [ ] colours
• [ ] strip_ext
• [ ] write_graph
• [ ] print_graph_attrs
• [ ] rand_int
• [ ] shuffle
• [ ] load_graph
• [ ] fix_percentile
• [x] calc_betweenness
• [x] calc_authority
• [x] calc_hub
• [x] calc_pagerank
• [x] calc_eigenvector
• [x] calc_degree
• [x] calc_modularity
• [ ] centralization
• [x] layout_graph
• [x] set_size
• [ ] create_filtered_graph
• [ ] shrink
• [ ] centralities
• [x] quickrunGraph
• [ ] filter_graph
• [ ] igraph_i_xml_escape
• [ ] igraph_write_igraph_gexf

[greebie]

Partially resolved with dc7e5f3fe736a1697e835c977468952697202fe5, 8d5133c9a7ca7c41da7dd1775d2a9363125ac665, and c0e0cc6338509c4284718a4496c42da6d231aecf.