Premises, goals and neg_premises of the task can now be shown directly on
the source code.
Notification Task was extended with a list of couple location, color.

temporarily the Why3 command is called 'newreplay'

adding the replay command in command line

- removed a temporary harcoded setting of steps limits
- allow reply to replay only obsolete proofs

Removed unnecessary duplications of cont_from*

on cross button.

print the backtrace and exit. Formerly, the exception was caught by GTK.

which holds the changed state of the source file.
To be improved.

Slightly improved debug error for node_change

Conflicts:
	src/printer/why3printer.mli