fix for fdo#55875 numbers as text converted strangely

old code used to use XCell->setString, new code uses rDoc.SetString which by default tries to detect number formats. The ScColumn::SetString that eventually
gets called seems to do lots of additional checks ( and apparently even if
an ScSetStringParam instance with mbDetectNumberFormat ( false ) was passed
it seems that it will still try to detect decimal number formats. With that
in mind I restore and un-unoified version of what XCell->setString used do

Change-Id: Ifaef74c78b198f492a390a3d5dc1721622a01ea4

sc/source/filter/oox/worksheethelper.cxx

@@ -1543,7 +1543,14 @@ void WorksheetHelper::putString( const CellAddress& rAddress, const OUString& rT
 {
     ScAddress aAddress;
     ScUnoConversion::FillScAddress( aAddress, rAddress );
-    getScDocument().SetString( aAddress.Col(), aAddress.Row(), aAddress.Tab(), rText );
+    ScBaseCell* pNewCell = NULL;
+    ScDocument& rDoc = getScDocument();
+    if ( !rText.isEmpty() )
+        pNewCell = ScBaseCell::CreateTextCell( rText, &rDoc );
+    if ( pNewCell )
+        rDoc.PutCell( aAddress, pNewCell );
+    else
+        rDoc.SetString( aAddress.Col(), aAddress.Row(), aAddress.Tab(), rText );
 }
 
 void WorksheetHelper::putRichString( const CellAddress& rAddress, const RichString& rString, const Font* pFirstPortionFont ) const