Remove create_project feature flag

- Removes CSS styles that are unnecessary with the new
  django-bootstrap-form
Don't allow blank project names

- Also adds a validator for target_date in the form definition, where it
  belongs.
Navbar fixes

- Navbar now collapses when necessary
- Navbar doesn't overlap content anymore
Merge pull request #93 from nikolas/enable-create-project

Remove create_project feature flag
Merge pull request #94 from nikolas/dont-allow-blank-project-name

Don't allow blank project names
deal with merge conflicts
Merge branch 'nikolas-navbar-fixes'