Fix the scrollbars not working

## WIP Do not merge

Added the first part of the fix, adding a small space
to the bottom of the full size datagrids therefore
allowing both scrollbars to be enabled, yet the bottom
one is not in the way as it is above the space. Only
problem still lies with embedded datagrids as the
size is fixed and does not apply the padding.

issue: A24Group/Triage#3766