Bug 21506: DataTables four button pagination uses the wrong icon for First and Last...

Bug 21506: DataTables four button pagination uses the wrong icon for First and Last buttons

Pages with DataTables' four button pagination use the wrong
icon for 'First' and 'Last'. Also, the icons for all four
buttons are truncated at the bottom.

This patch fixes that.

Test plan:
1) Go to a page that uses four button pagination (e.g. Home >
   Administration > MARC frameworks) and notice how the
   pagination icons for First/Previous and Next/Last are the
   same. Also notice all four icons are clipped at the bottom.
2) Apply the patch.
3) Refresh the page; the First and Last buttons' icons now
   include a vertical bar, and there is no clipping visible.
4) For completeness, check other affected pages as well.

Signed-off-by: Séverine QUEUNE <severine.queune@bulac.fr>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>