Section out internal ctls into a different file

These settings are internal and are not needed by normal users. They are
in the public API because they are used by some SDKs for various reasons
and thus are not unsupported or deprecated; however it is unhelpful to
have them in the listing among the settings a user might actually care
about.

The settings hidden are:

* MEMDNODE_INFO, CONFINODE_INFO - these expose too much information
  about the nodes. Additionally they don't actually contain sufficient
  information about whether a node is a master, replica etc. With the
  new vbucket API this information is already available from there.

* IOPS_DEFAULT_TYPES - Knowing the default I/O settings is useful for
  tests that use various I/O plugins but doesn't concern most users.

* CONFIG_HTTP_NODES, CONFIG_CCCP_NODES, CONFIG_ALL_NODES, REINIT_CONNSTR
  These features may be useful in theory, however they are only
  guaranteed to work up until the first call to lcb_connect. This big
  caveat removes its usefulness for most use cases concerning users.

Change-Id: I3a1b4ab5aca1a7a54b957dd88077746ce57606c9
Reviewed-on: http://review.couchbase.org/39455
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>