Bug 13994: Add a back link to error message in Reports

Bug 13994: Add a back link to error message in Reports

To reproduce:
- Go to Home > Reports
- Create from SQL
- Do something that results in an error message, e.g. by entering an UPDATE statement

Result: You get an error message with title "The follwing error was encountered"
But there is now link to go directly back to fix it.

To test:
- Apply patch
- Repeat steps above
- Verify that a link appears (and works): "Back to previous page"

Signed-off-by: Nick Clemens <nick@quecheelibrary.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>