Fixed a Jenkins build warning about unused variables
Modification to SourceGrid to help us with our wrapper event DoubleClickHeaderCell.  By changing the double click method we created a consequence that the autoSize on double click when on the cell boundary not only performed the autosize but also applied the sort to that column.  This change puts some additional logic into the grid that sort no longer happens if the mouseDown was on the cell border therby initiating a column resize.  This is good for the grid anyway, and certainly helps us!
A further merge from Branch 'lp:~alan-paterson/openpetraorg/dev0001853_dec2013_release'.