fpspreadsheet: Fix incorrect characters in label cells read from of ods files. Partial fix of negative values forgetting the red color in case of built-in format nfCurrencyRed.

git-svn-id: http://svn.code.sf.net/p/lazarus-ccr/svn@3188 8e941d3f-bd1b-0410-a28a-d453659cc2b4