deposit: display fixes

* Fixes the layout without touching the .container class
  from core Bootstrap and set proper breakpoint

* Adds new styles for the Instructions box

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>
A separate commit for fixing the bug that introduced accidentally by this commit 0089073 is redundant. Either you amend the commit or either you review better next time. :smiley: