Add tasks partial. Linkify project names in tasks index.
Fix spec
Update README
Add completable concern
Move active scope to completable as class method, rename it incomplete
Update show views to use incomplete
Fix broken tests
Update rails and friends to 4.0.0.rc1
:encrypted_cookie_store to :cookie_store
Spruce up specs
Merge branch 'feature/view_tasks_by_project' into develop