KohaREST alternate driver

Hi Demian, VuFind Team,

We've been working on a revised KohaREST ILS/Driver for VuFind for some of our customers. Not all expected features work yet, as they depend on enhancements to the Koha API that we're still in the process of developing, but we have tested quite a lot of the funtionality and by and large things seem fine.

I thought I'd share this with you already for early feedback — let me know if you spot any faux-pas or grievious errors!

Best wishes,

Alex