Log Message:
Update databases/couchdb to 1.2.0.

Changes in 1.2.0
* Updated bundled erlang_oauth library to the latest version.
* cURL is no longer required to build CouchDB as it is only
  required by the command line JS test runner.
* Added a native JSON parser.
* Optional file compression (database and view index files). This feature
  is enabled by default.
* Several performance improvements, especially regarding database
  writes and view indexing.
* Added a 'data_size' property to database and view group
  information URIs.
* Added support for automatic compaction. This feature is disabled
  by default, but it can be enabled via the .ini configuration.
* A new replicator implementation that offers more performance
  and configuration options.
* Added optional field 'since_seq' to replication objects/documents.
* Simpler replication cancelation.
* The _active_tasks API now exposes more granular fields for each
  task type.
* Futon's 'Status' screen (active tasks) now displays two new task
  status fields: 'Started on' and 'Updated on'.
* Added built-in changes feed filter '_view'.
* Fixed old index file descriptor leaks after a view cleanup.
* Performance improvements for the built-in changes feed filters
  '_doc_ids' and '_design'.
* Fixes to the '_changes' feed heartbeat option when combined with
  a filter. It affected continuous pull replications with a filter.
* Fix use of OAuth with VHosts and URL rewriting.
* OAuth secrets can now be stored in the users system database.
* Documents in the _users database can no longer be read by everyone.
* Confidential information in the _replication database can no longer
  be read by everyone.
* Password hashes are now calculated by CouchDB instead of the client.
* Allow persistent authentication cookies.
* The requested_path property of query server request objects now has
  the path requested by clients before VHosts and rewriting.
* Fixed incorrect reduce query results when using pagination parameters.
* Made icu_driver work with Erlang R15B and later.
* Improvements to the build system and etap test suite.
* Avoid invalidating view indexes when running out of file descriptors.
* Log correct stacktrace in all cases.
* Improvements to log messages for file-related errors.