Prevent potential XSS in unescaping escapeddict
Add pushplan to create Conflicts column in db

Add SQL commands needed to create / rollback the 'Conflicts' column in
the push_requests DB field.
Remove double-negative no_requeue

Make naming more sane by replacing "if not no_requeue" with "if requeue"
Remove commiting from GitMergeContextManager

Instead of performing a merge within the __init__ of the GitMergeContextManager,
only create the state needed for the merge to happen, and break merging out into
it's own method.
Add thorough submodule conflict detection

Fully flesh out submodule conflict resolution based on the merge-branches push
helper script.