Add options for display disabled and selected options
Create a method for deciding whether or not search results should be
included based on current options and parameters.
Make sure we always show selected results on single selects.
Only show groups that have active options.

This change accounts for groups that are filled _only_ with
selected/disabled results when those options should not be displayed
Include groups in search results only if they have active options.

This fixes a bug where a group shows up, but has no displayed options.
Always mark options as not a search match at the start of the test.
Move group and option tests to their appropriate method.
Add documentation for the new options.
The default for these options is actually true. D'oh.
Merge branch 'master' into optionally-show-selected-disabled
Update default text to reflect the correct behavior.
Merge pull request #1404 from harvesthq/optionally-show-selected-disabled

Option to Hide Selected & Disabled Options