adds css for all plugins, and adjusts todo list.
abstracts some logic when dropping items into regions so we can adjust for snippets.
more adjustments to the focusout code that attempts to keep focus to within modals/dialogs.
adds a start to an example plugin that I'll build out as a more advanced color picker.
adds initial snippet region that will be used during the build out of snippets.
adds update event for modal and styles h3's.
adjusts form handler to understand models (will be used by snippets, and may effect how some plugins are done).
adds initial snippet implementation.
minor css adjustments.

- zindex for floating interface
- a transition for the body top if it has a mercury-transitions class (which makes showing/hiding the interface nicer with non-floating interface).