Now also includes natural sorting for author, topic, theme & CCLI number as well
Also refactors Songbook Search to make the database do filtering for performance rather than querying all then filtering
I've tested it on my database of 500-odd songs and it seems a little faster
Includes unit tests
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lp:~minkus/openlp/naturalsortsongs (revision 2519)
[SUCCESS] https://ci.op...
bzr-revno: 2637
Fixes: https://launchpad.net/bugs/1280295