Final touches

* .gitignore

* doc/GIS_Raport_koncowy-MOlszewski_TPieczerak.tex -> doc/GIS_Raport_koncowy-Kruskal-MOlszewski_TPieczerak.tex
Final documentation.

* doc/com_chart.png
New chart.

* main.c
Changed mst prefix to suffix.

graph_format.txt -> graph_format.gf
testing/graph_example1.txt -> testing/graph_example1.gf
testing/mst_graph_example1.txt -> testing/graph_example1.gf.mst
testing/graph_example2.txt -> testing/graph_example2.gf
testing/mst_graph_example2.txt -> testing/graph_example2.gf.mst
testing/graph_example3.txt -> testing/graph_example3.gf
testing/mst_graph_example3.txt -> testing/graph_example3.gf.mst
Renaming due to changes in main.c and changing graph file extension to
".gf".