Label validator unit tests

Wrote some unit tests to check the recent fix to the label validator
adding iptables -L output to the katello-debug
API - Moving Systems index API controller to using Elasticsearch.

This starts a migration to allowing complex search queries through the
API by hooking into the Elasticsearch index for a model.  This is a port
from the setup that the UI controllers are using to render chunks
of items.
API - Moves the Elasticsearch items query to be a class and changes
Systems index API to it's use.  Adds a paged and page_size option
for the UI to use and maintain the current standard of returning
all results for API calls.
API - Updating documentation and cleaning whitesapce.
API - Updating API sytems controller spec tests.
Merge pull request #1715 from ehelms/system-index-elasticsearch

System API Index Elasticsearch
Standardizing notification message for re-using Labels. Fixes #1718
Merge pull request #1688 from daviddavis/flv

TDD: Added some tests for the fixed label validation
Showing invalid label as error not exception. Fixes #1721
Merge pull request #1719 from omaciel/standardlabelnotif

Standardizing notification message for re-using Labels. Fixes #1718
Fixes #1658 - Removes all user notifications regarding login due
to redundancy and adds a helptip style message on the dashboard
for users without access to any organizations to let them know what
their next steps are.
Merge pull request #1723 from ehelms/issue-1658

Fixes #1658 - Removes all user notifications regarding login due
Merge pull request #1722 from daviddavis/1721

Throwing error on bad label and not exception
Merge pull request #1710 from lzap/debug-iptableas

adding iptables -L output to the katello-debug