- enables alternative testing frameworks to include AV::TC::Behavior
  instead of subclassing AV::TC
- also added tests and code for:
  - test view delegates :notice to request.flash
    - useful since generators generate views that use notice
  - test case doesn't try to include modules that are actually
    classes
Signed-off-by: NJosé Valim <jose.valim@gmail.com>