Support _all_docs in list functions through clustered interface
Allow optional max_uri_length server setting
Allow cacertfile without verifying peers

COUCHDB-2028
Support for user configurable SSL ciphers
Support `fail_if_no_peer_cert` ssl option
Pass context to all_docs
Add support for eventsource changes feeds
Send eventsource heartbeat event
Support Last-Event-ID header for eventsource changes feeds

COUCHDB-1852