(#2400) - add settings for firefoxos
(#2427) - minor grammar correction
(#2391) - improve idb bulkDocs perf

Improve the performance of bulkDocs in idb
by optimistically inserting into the by-seq
store and then recovering from the
rare error only when necessary.
(#2392) - improve websql bulkDocs perf

Basically the same optimization as #2391,
but for websql. Also added a test for sanity.
(#2393) - correct update_seq with successive new_edits
(#2146) rename pouchdb-nightly.js to pouchdb.js
(#2414) - Add note for the complete event used  with live changes
(#2430) - bulk documentation