Several changes in Kruskal alg.
- Input object interface was changed to an STL compatible one.
- template parameters of class KruskalPairVec has been simplified.
- (the most of) the names meet the naming conventions.
- a lot of (but still not enough) documentation has been added.
- class KruskalMapVec has been commented out.

hier: hierarchygraph.h hierarchygraph_test.cc

	g++ -Wall -W -I../.. -I../klao -I../../hugo hierarchygraph_test.cc -o test

edge: edgepathgraph_test.cc edgepathgraph.h

	g++ -Wall -W -I../.. -I../klao -I../../hugo edgepathgraph_test.cc -o test