Inital RiakCS docs for OpenStack API support

Reorganize RiakCS storage API docs and add a page to show the
supported features of the OpenStack API.
Add placeholders for OpenStack API description pages
Fixed port numbers in examples and an out-of-date reference to 1.3 repl.
Update OpenStack API operations pages to replace placeholders with actual content
Merge pull request #525 from basho/hc-repl-config

Port number and repl version fixes to Enterprise section
Added sample replication hook to "Repl Hook Guide"
Incorporated Edits
Linked riak_object and corrected send_realtime/2

Added version dependent links to the source of riak_object. Corrected
the narrative for send_realtime/2 to include the information about
returning a list to "pre-replicate" objects that the current object
might depend on.
Update and clean up vm.args docs
Updates based on feedback from @dp. Also eliminate a superfluous non-header header
Fix bad install link for 1.4.0
Also update filename
Add install link from downloads
Reference to old PBC Index documentation needs to remain the same.
Clean up aws tweaks
Added csharp stuff
Randomly jiggling things
Cleaned up language in PR

* Moved CSharp Taste of Riak to community driven library list
* Clarified language in CSharp Taste of Riak
Adjust Taste of Python to be consistent with the new client setup.
Update client features matrix with latest python features.