minor changes for g++ 4.7 compile
Merge pull request #2 from pederico/master

minor changes for g++ 4.7 compile
Add swig dependency
Update swig path
Add python dependency
Add python development package dependency
Update Python include path
Add -fPIC flag
Fix PIC flag
Replace stdlib.h with cstdlib
Merge branch 'pederico-fix' of github.com:marcusps/GraphSim into pederico-fix
Merge pull request #3 from marcusps/pederico-fix

Get Travis build working, include other fixes from pederico