* [CHD-3572] [Snippets] Added an 'updated' field to snippet records.  This makes it easier to identify changed snippets from the UI, and enables syncing through the API.
* [CHD-3632] [UI/Accessibility/Search] The global search menu can now be accessed using the TAB key for vision-impaired users.  Previously the menu only opened with a mouse 'hover' event, but it now responds to clicks (and ENTER) as well.  When clicking or pressing ENTER, the first item in the search menu will be focused automatically.
* [CHD-3629] [Setup/Branding] When setting a logo or favicon URL from Setup->Configure->Branding, the URLs will be tested before they are saved.  Some users were entering URLs without a scheme (e.g. example.com/logo.png vs. http://example.com/logo.png) and having trouble.
* [CHD-3635] [Mail/Compose] Tickets can now be opened without any recipients, and the form will act like the "Start a new conversation without sending a copy of this message to the recipients" option was selected.  This creates a ticket record without sending any mail.  Several users have asked for the ability to create tickets as the result of phone calls or Twitter messages without requiring an email address.
* [UI/Usability/Popups] Popup windows can be resized again, and they'll respect a maximum height of 85% of the browser window.
6.6.1-release checkpoint
Merge branch '6.6.1' into stable