Issue #31
NumericDataGridViewColumn, NumericDataGridViewCell & NumericEditingControl added to manage numeric columns in DataGridViews.
DataGridViewWithPaste.OnCellParsing implemented to handle NumericDataGridViewColumn values that have been cleared. In such cases the value is set to null.
Issue #31
Numeric DataGridView columns changed to use GMS_Library.Controls.NumericDataGridViewColumn so that only numbers are accepted.
Issue 17 - Comments column added to Payments and Refunds grids.

Issue 31 - Numeric DataGridView columns changed to use GMS_Library.Controls.NumericDataGridViewColumn so that only numbers are accepted.

Issue 33 - ProduceNonSARProjectMilestoneReport - "Chief Investigator:" heading is now "Contact Person:" for all Organisation Types except Research.