WIP on 3272-db-config
adding db-level reconfigure
Merge branch 'reql_admin' into tim/3272-db-config

This commit still doesn't compile (tim/3272-db-config didn't compile before, so it's OK)

Conflicts:
	src/clustering/administration/real_reql_cluster_interface.cc
	src/clustering/administration/real_reql_cluster_interface.hpp
Make db_config() porcelain work.
reconfigure changes
fixing bag comparison in js polyglots
updating tests for reconfigure optargs
adding tests for reconfiguring all tables in a database
Declare single-parameter constructors explicit; fix typo in comment.
Don't try to use table_meta_read() for db_config
Fix style issues in interface.db_config test.
Merge branch 'tim/3066-acks-durability' into reql_admin
Merge branch 'reql_admin' into tim/3268-3269-table-status
Merge branch 'tim/3272-db-config' into reql_admin

Conflicts:
	drivers/python/rethinkdb/__init__.py
Add split_points field to rethinkdb._debug_table_status.
adding waiting for namespace interface readiness
adding dummy rdb_protocol reads and writes
changing namespace interface wait_for_readiness to poll - more reliable
using namespace_interface wait after table_create
fixing review comments in wait_for_readiness