Resolve issue with hiding field names

Hide field names unless they're titles.
Merge branch 'master' of https://github.com/cluke009/CMB2 into cluke009-master
show_on_cb now works for groups
Merge branch 'master' of https://github.com/cluke009/CMB2 into cluke009-master
restore repeat group title bg color
Add helper function to update an option
Break up unit tests and add for new function
update styling for repeatable group headings, and add close button to title bar
make repeat group toggle work in sidebar too
Merge branch 'cluke009-master' to allow collapsible repeat groups. Props @cluke009.
Merge branch 'option-update-helper' of https://github.com/mAAdhaTTah/CMB2 into mAAdhaTTah-option-update-helper
update .pot for new line numbers
Remove unecessary $resave variable.
Update docblock descriptions to be more rational
Merge branch 'mAAdhaTTah-option-update-helper', "Add helper function to update an option". Props @mAAdhaTTah.
Merge branch 'issue/42' of https://github.com/marcusbattle/CMB2 into marcusbattle-issue/42
update .pot line-numbers
Merge branch 'marcusbattle-issue/42', "show_on_cb now works for groups". Props @marcusbattle.
Merge pull request #48 from mustardBees/patch-1

Resolve issue with hiding field names. Props @mustardBees.
Revert mustardBees/patch-1 because of broken unit tests