Resolved #139: Use project query string for staging

To aid the users in finding and managing stages we are pushing the stage
query params directly into the project query search box. Existing
queries are updated when selecting a new stage.

This is useful for toggling through various stages for a particular
search phrase.
Resolved #141: Gemfile upgrade to Rails 3.2.16

Bug and security fixes.
Removed state from project

Also disabled harmful migration tasks.
Log project stage transitions

Closes #136. Projects controller creates transition memo with every
project stage change. Transition model includes separate old_stage and
new_stage fields. Text body is simply "Project stage changed from
shipped to completed."

No user is allowed to edit transition memos.
Project stage improvements