Bug 17783: Test to print performance of get_effective_issuing_rule

Bug 17783: Test to print performance of get_effective_issuing_rule

This test prints the amount of issuing rule matches per second for
1. worst case, when non-existent branchcode, categorycode and itemtype is
   being searched (currently 8 queries)
2. mid case (rule found on 4th query)
3. 2nd best case (rule found on 2nd query)
4. best case, when an issuing rule is defined for exactly those branchcode,
   categorycode and itemtype (currently 1 query)

To test:
1. Run t/db_dependent/Koha/IssuingRules.t
2. Write down the per-second amount to compare with next patch

Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>