Watch hot-table directive's settings and update the underlying handsontable in response to changes

I am working on a project that requires requires the hot-table directive to re-render in response to arbitrary changes in its settings (not just changes in columns and datarows attributes, but other settings including width and height).  I noticed this was not the current behaviour for any settings beyond columns and datarows.

This change updates the hot-table directive to watch for changes in other settings using the $watchCollection, and triggers the underlying handsontable settings to be updated in response.

Thanks for all your good work on ngHandsontable.