Add CSV River, SegmentSpy and Inquisitor plugins
Reformat Client list into per-language sections

The Client list was getting unwieldy and difficult to navigate. This pull
request reformats the list into per-language sections. Additionally, a new
section has been created (Health and Performance Monitoring), which now
includes plugins like bigdesk, SPM and nagios-related.  This moves them
out of Misc. which is less descriptive.

Lastly, these have been added:

- es2unix
- dangle (closes #379)
- SegmentSpy
- check_elasticsearch and opsview-elasticsearch (closes #372)
- Inquisitor
- Sherlock
Merge pull request #383 from polyfractal/update-plugins-page

Add CSV River, SegmentSpy and Inquisitor plugins
Merge pull request #382 from polyfractal/reformat-clients-page

Reformat Client list into per-language sections
Removed the link to community Chef cookbook, add correct link

The old Elasticsearch cookbook on the Opscode site has been replaced by
http://github.com/elasticsearch/cookbook-elasticsearch.

Related: elasticsearch/cookbook-elasticsearch#47
fix links to elasticsearch-head plugin
Merge pull request #384 from mobz/master

fix links to elasticsearch-head
Improved documentation for nodes stats
Update Index Analysis (Indices Update Settings API)
Fix sort_order to order in sort examples
Update plugins.textile with View Plugin
Merge pull request #388 from tlrx/patch-5

Update plugins.textile with View Plugin
Update statistical-facet.textile

Typo fix
Fixing 'bazzarvoice' typo
Merge pull request #390 from victortrac/master

Fixing 'bazzarvoice' -> 'bazaarvoice' typo
Merge pull request #389 from ash211/patch-6

Update statistical-facet.textile
Add Clojure Language Plugin
Update clients.textile

Added elasticutils to Python clients list.
Tidy up Guide contents
Move the glossary into Reference
Remove Intro, Concepts, Build from Source
Make Clients & Integrations top-level
Moved the clients folder to the same level as reference/