Update pog icon to a delta symbol.
More PO list column tweaking.
Initial working implementation of Isabelle session kill.
Remove unused imports.
Merge remote-tracking branch 'origin/development' into newpog
Remove assistant calls from CmlLexNameToken.

This means a new (possibly less eficient) way to compute name token hashcodes.
But it has to be done since we will not thread assistant factories into name
tokens.
Replace static calls to PAccessSpecifier astnt with factory calls.
Thread assistant factory into PTypeSet constructor.

This copes with the latest changes to the overture assistant mechanisms.
Merge remote-tracking branch 'origin/development' into ldc/astntrw
Merge remote-tracking branch 'origin/development' into newpog
Merge remote-tracking branch 'origin/ldc/astntrw' into newpog
another try at fixing the cosim process tests
improved the main test case class in the interpreter to handle exceptions better
close #244 the problem was only visible if a project wasn't type checked (no open files). Added type check, check to the launch tab before opening process selection dialog.
close #257 added flag to handle the animation checkbox behaviour correctly.
improved error reporting in interpreter tests when the test has type errors. TC was missing a flush on the streams
fixed #260 A clone has been added to allow for re-use of the action body.
fixed #250 deepcopy faild of the context because ChannelNameSetValue returned null in clone.
Merge remote-tracking branch 'origin/kel/base' into development
Merge remote-tracking branch 'origin/ldc/astntrw' into development