fixed CMSfields js and css issues
Now uses GridFieldExtensions for the sortable rows
Implement getFilename and getName to stick comparely to File API.
FIX: Resolve issue of not being able to attach documents on draft pages
Make DMSDocument methods chainable. PHPDoc cleanup.

- Remove unimplemented getAllTags()
- Add .DS_Store as ignored file
- Add gridfieldextensions as a declared dependancy.
FIX: browse by page dropdown is unusable. (Fixes #26)
Sort assets by ID so matching '2' doesn't first match newer records
Added the Header component back in
Merge pull request #43 from Leapfrognz/patch-1

Added the Header component back in