Refs #3809 - Remove cops for empty lines

Fixes #7233 - Drop Ruby 1.8.7 and revert Ruby 1.8.7 specifics

Refs #3809 - Remove rubocop TODOs

Removed the following TODOs so that cops for these will run from now on:

Lint/AmbiguousOperator, DefEndAlignment, DeprecatedClassMethods
EnsureReturn, RequireParentheses, Void, BlockAlignment, EndAlignment,
UselessAccessModifier,...

Fixes #7738 - logout_url is nil by default for all SSO backends

fixes #7737 - no specific logout URL needed, will go directly back to login.

Fixes #3840 - Removes unused Signo related code

fixes #6964 - replace default scope that hides users with explicit scope

fixes #3272 - allow 'admin' account to be removed and replaced

fixes #3892 - process REMOTE_USER_GROUP_N and REMOTE_USER_GROUP_#, add user to groups based on external user groups.

fixes #4462 - extending the /users/login handling to process REMOTE_USER through intercept