Issue #102: Add scripting-definition support

'MonticelloFileTree-Core-topa.163' message 'Issue #102 Add scripting-definition support'
'MonticelloFileTree-Tests-topa.43' message 'Merge. Add tests for Issue #102: Scripting definitons'
Squeak does not yet like underscore selectors by default *sigh*
Fix Squeak-Trunk part.
Merge pull request #102 from krono/krono/issue_102/squeak4.3

Script support