fpspreadsheet: Fix fpsgrid demo showing an incorrect backgroundcolor of new spreadsheets.

git-svn-id: http://svn.code.sf.net/p/lazarus-ccr/svn@3159 8e941d3f-bd1b-0410-a28a-d453659cc2b4
fpspreadsheet: Fix selection of short and long date formats in fpsgrid demo

git-svn-id: http://svn.code.sf.net/p/lazarus-ccr/svn@3160 8e941d3f-bd1b-0410-a28a-d453659cc2b4