rename function for better readability

git-svn-id: svn+ssh://svn.abisource.com/svnroot/abiword/branches/gsoc2013tables@33416 bcba8976-2d24-0410-9c9c-aab3bd5fdfd6
fix some corner condition

git-svn-id: svn+ssh://svn.abisource.com/svnroot/abiword/branches/gsoc2013tables@33417 bcba8976-2d24-0410-9c9c-aab3bd5fdfd6