LDEV-1410: When a description wasn't supplied for a lesson, a default description was always set. The default has been removed. I've also improved the handling for a missing lesson title, but it will probably never be used as Flash ensures there is a lesson title.
LDEV-1285: Adding a new Activity type "Options With Sequences" so the Flash will know whether to expect sequences or not. The type is stored in the database otherwise we won't know which type it will be if the user saves the Optional without any child activities. The back end treats all Optional activities the same.
LDEV-1285 Adding activities to sequences from canvas now resizes sequence panels correctly in align with parent optional sequences activity container width (which is updated).
LDEV-1285 Set defaultActivityUIID field (firstActivityUIID in flash) for Sequence Activities in Optional with at least 1 Activity in the Sequence. Updated DDM to return empty Sequences in save (storage) packet.
LDEV-1250 add lesson completed icon to display alongside lesson (todo: the icon); also moved disabled/archived labels to an icon. currently uses an existing icon.
