(#2494) - fix local doc get/put/delete
(#2517) - don't mutate host.headers
(#2517) - add test for mutated headers
(#2519) - increase selenium timeout
(pouchdb/mapreduce#191) - add migration test
(#2469) - blog post about PouchDB + LevelUP
(#2466 #2475) - replicate using changes with include_docs

Also, to fix #2475 we use open_revs="all"
so that the URL is not too long.