Update pog icon to a delta symbol.
More PO list column tweaking.
Initial working implementation of Isabelle session kill.
Remove unused imports.
added more tests for TC #243
close #255 requires sync with overturetool/overture@dcc7545bda6a266ca39d84313e38d7cb2bdd64a6
Merge remote-tracking branch 'origin/test' into kel/base
Merge remote-tracking branch 'origin/test' into kel/base
changed the interpreter external cosim test cases. with the console matching
Merge remote-tracking branch 'origin/development' into newpog
Check parsed function signature type to ensure it's actually a function
type, otherwise throw a StuckException.
Fix #229, Fix #256
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
Analysing Insiel's example from Paolo.