Adding fullscreen presentation mode.

Change-Id: Id07416ce204d1d7dd917fbd33a4d9f5072ac1703
Reviewed-on: https://gerrit.libreoffice.org/38006Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>
Tested-by: Tomaž Vajngerl <quikee@gmail.com>