Issue #48 Applying refactorings makes the java editor jump to the start of the file

Using Eclipse file buffers solved the problem.
Issue #32 Add a CFG (Control Flow Graph) builder

CFGBuilder.java:
Switched to a new implementation.

*.dot:
Consequence of the change above.

CFGEdgeBuilder.java:
Added a new sanity check to avoid building twice the same edge.

CFGDotPrinter.java:
Fixed a bug where the updaters of a loop where not belonging directly to the subgraph of the loop.