Add test coverage for sqlite regexp function
Add test coverage for sqlite regexp function

Add some tests which for the regexp function which we install for
sqlite.

Need test coverage to catch e.g. a regression of the fix for
bug #1031846.

Change-Id: I4bd77d0d93c4fc85588e6e6d5a559e68133dbf73

JioCloud/oslo-incubator,JioCloud/oslo-incubator,JioCloud/oslo-incubator