Removed unused imports and did some minor pep8 cleanup.
Minor cleanups

 - Removed unused imports from several files
 - Fixed linter errors (operand spaces, etc)
Revert "Removed unused imports and did some minor pep8 cleanup."

This reverts commit 154f82711691bb34059c4f21dd97b1defbce1f4c.
Merge branch 'cleanups'

* cleanups:
  Minor cleanups
Merge pull request #4 from induane/master

Removed unused imports and did some minor pep8 cleanup.