Cms::Blocks need to handle standard Files as well

This is required to get page file fixtures working.
Updating test expectations to handle the new tag in the example fixture
Adding the ability to have page_file fixtures and haml fixtures with their proper extensions.
updating schema to have polymorphic blocks
Updating fixtures and adding base relationship to page/blocks
Blocks are now polymorphic and all tests are passing
Moving block logic into a module
Moving more methods into acts_as_cms. All tests are passing.
Setting an explicit class_name

Rails apps that use the cms_acts_as_cms extension need to have an
explicit class_name set, otherwise, they assume the wrong namespace.
explicit class_name for revisions
Moving more page references to block able.

This helps with form builders for the cms_acts_as_cms extension
Updating the form builder to support different types of field names
Removing cms_has_revisions_for and updating the module name
Merge pull request #408 from Emerson/feature/page_file_fixtures

Feature/page file fixtures
wording
Merge branch 'master' of github.com:comfy/comfortable-mexican-sofa
Adding upgrade migration
Merge branch 'master' into feature/acts_as_cms
Pre-merge cleanup
some tests for html/haml and file imports