Update docs.o.o/developer/language-bindings.html

Remove obsolete link to API Quick Guide, replace it with links
to User Guide and Admin User Guide

Add Heat and Ceilometer clients

Redirect python-quantumclient documentation to python-neutronclient

Change-Id: I6cdf5cd107383688192ede6d08a4f18f4c51eb87
Clarified example architectures

Updated the associated 'master' patch after review cycle changes to
the 'havana' patch.

Change-Id: I5ab35042afdb4c76490b5a1c460e875c11ea24d8
Partial-Bug: #1263719
Merge "Clarified example architectures"
Merge "Update docs.o.o/developer/language-bindings.html"