RDE first crack.

We've introduced a Rapid Data Entry button to tree's toolbar. This invokes a modal with a horizontal form.  There are some keyboard shortcuts enabled with the 'shift' key (namely arrows to navigate and return to add new row).  

Headers can be toggled as 'sticky'.  When adding a row, values from the current or last row (depending on button clicked) are used to populate any sticky columns in the new row.

Frontend hits two new endpoints for adding children to either a Resource or an Archival Object.  There's also a new JSONModel object to help build the data required for this task.

Still to do... clean up the I18n for any labels etc.  Clean up the errors. 

Would be good to check to see we're on the right track before we polish.