TC: MOVED DIV WRAP CODE FROM Provider to Context

The div wrapping code that facilitates in-line editing has been moved
from the Provider class into the new Context class. This was done so
that post-process parsing can happen after rendering but before the div
wrapping to prevent the div wrapping from being sent to post-process
parsing. Now markdown is properly rendered and can also be edited.

TODO:

With this new design, some other aspects of Provider/Controller code
might be rethought (such as maintaining separate raw/wrap Template
objects) however this has not been done yet because not-exist templates
and error templates haven't been refactored yet.