Remove some unused imports/variables.

A batch of unused imports are removed. Unused variables are either removed, or commented out
if they are referenced in pre-existing comments. Files not modified include tests or ast files.
Reference static members with qualified type name.
Merge pull request #22 from cabernal/fix-static-refs

Reference static members with qualified type name.
Merge pull request #21 from AndrewFerr/unused_things

Remove some unused imports/variables.
Improved the way that the interpreter location is shown on the pydev package explorer.
Removed println.
Improved jython scripts so that it only creates the needed classes when the script is compiled the first time, not on every new editor.