External DB listener test

- Goes a little bit beyond just making sure 5432 is open and
  also sanity-checks the miq_databases table
Merge pull request #171 from seandst/test-appliance-db

External DB listener test
Added test for documentation

Simple test for availability of documentation, iterates each link and
requests head, requires a 200 Status code
Adding Version test on Configuration -> About page
Merge pull request #174 from psav/testing_docs

Added test for documentation
Merge pull request #173 from psav/testing_version

Added testing of version number against new yaml data