fpspreadsheet: Complete write/read unit tests for insert/delete of columns and rows in biff8 and ooxml files having merged cells.

git-svn-id: http://svn.code.sf.net/p/lazarus-ccr/svn@3596 8e941d3f-bd1b-0410-a28a-d453659cc2b4
fpspreadsheet: Make sure that all test units are added to the cli test suite.

git-svn-id: http://svn.code.sf.net/p/lazarus-ccr/svn@3597 8e941d3f-bd1b-0410-a28a-d453659cc2b4