Fixed api-endpoints Purpose capitalization; added tests for Purpose and Doc for all commands
Merge pull request #904 from dimitern/api-endpoints-fix-help

Fixed api-endpoints Purpose capitalization; added tests for Purpose and Doc for all commands

The "api-endpoints" command's Purpose doc lowercased.
Added a test to validate the format of all commands'
Purpose and Doc fields (proper capitalization and makes
Purpose required). Only "api-endpoints" is affected by
the test so far.