Cleanup editor functionality and code

Make the content model proxy all events for its currentPage
so that views can listen directly to the model rather than trying
to juggle events for pages.
Upgrade to require-handlebars-plugin 0.10
Update URL when title of content changes
Don't show an outline around buttons
Trigger a current page loaded event if there is no page to load
Properly detect when content has finished loading
Don't use whitespace removal because it is triggering an odd bug
Remove dead code
Don't report content as editable until it has finished loading
Don't proxy general change events on the current page
Mark pages and books as editable on load if they are drafts
Appropriately detect if the current page is editable
Fix header loading when not in a book
Remove dead code
Redraw view when content has loaded
Properly detect if content is editable
Only append the version to the url if it exists
Remove unnecessary null check
Ensure isEditable always returns a boolean value (not undefined)
Appropriately detect if the content is editable