execute: use xsd:int for cell value type

because webpivottable only understand this

olapy/core/services/xmla_execute_tools.py

@@ -341,9 +341,10 @@ class XmlaExecuteTools():
         for value in columns_loop:
             if np.isnan(value):
                 value = ''
+            # FIXME: Support different value types ( float )
             cell_data += """
             <Cell CellOrdinal="{0}">
-                <Value xsi:type="xsi:long">{1}</Value>
+                <Value xsi:type="xsd:int">{1}</Value>
             </Cell>
             """.format(index, value)
             index += 1