Merge pull request #5 from oster/master

just syncronizing
Mark as failed exercises if a program's interruption occurs (fix #224)
Edit displayed error message and fix ChangeLog
Merge pull request #377 from oster/fix-interruption-passing

Mark as failed exercises if a program's interruption occurs (fix #224)
fix a French typo (fix #378)
don't advise to port a lesson to lightbot, this makes no sense
Disable creative mode when switching the exercise (fix #380)
actually, creative is in the Exercise menu
rerun po4a
speedup the large worlds of Koch
give the pseudo code of the general case for the first recursive trees
speedup the large sierpinski worlds
mouse coordinates should be consistently in black
loosen the slope equality test, and display slope in debug mode
don't do lame tests, and don't fail either
let the details area grow to take any additional space
also merge lines that have the same end, not only the same start
detect when lines are included one within the other with no common extremities

Fix #381
Fix the name of a Scala entity (fix #383)
Fix a bug from GitSpy overwriting current files by the last result's ones when switching exercises