Revert "Check in progress on script property initialization (before GROOVY-7026)."
This work is going on in MEMOIZE and new GROOVYX branches.

This reverts commit c8919ec49a2ff5def86a7652033b0a101d7adabe.
Working again - basically by bypassing all the new construction jazz.
Use script field names (not CLI parameter names) for command arguments.
Clean up vararg treatment and check for undefined arguments.
Clean up directory creation and usage.
Stop tracking the idea workspace file.
Merge in GROOVYX stuff.  Restore .idea/workspace.xml cuz it has the run configs in it.
Restore IntelliJ workspace.xml cuz it has the run configs in it.