Adds keyboard bindings and associated help menu for selecting reminder type in bookmark modal, and pressing Enter to save.
Introduce the following APIs for `KeyboardShortcuts`:
* `pause` - Uses the provided array of combinations and unbinds them using `Mousetrap`.
* `unpause` - Uses the provided combinations and rebinds them to their default shortcuts listed in `KeyboardShortcuts`.
* `addBindings` - Adds the array of keyboard shortcut bindings and calls the provided callback when a binding is fired with Mousetrap.
* `unbind` - Takes an object literal of a binding map and unbinds all of them e.g. `{ enter: { handler: saveAndClose" } };`
New Reminder Types
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* Add a "later this week" reminder which is today + 2 days, will not show if we are on the days Thu-Sun
* Add a "start of next business week" reminder which is 8am Monday
Bugfixes and Tweaks
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* Move dates out of translation for reminder types and yield HTML for tap-tile for more customizable content and styling
* Make sure double clicking the bookmark icon in quick access takes users to the new bookmarks-with-reminders page
* Sane default to 8am (start of day) for custom reminder with no time
Based on issues identified in https://meta.discourse.org/t/improved-bookmarks-with-reminders/144542/20
* Implement the resolvedTimezone() function on the user model where we return the user's timezone if it has been set, or we guess it using moment and save it to the user using an update call if it has not yet been set. This covers the cases of users who do not log out/in often who will not get their timezone set via login. This also makes sure the guess + save is done in a non-obtrusive way not on every page -- only when it is needed.
* Before if a user's timezone was blank when they visited their profile page we were autofilling the dropdown with the guessed timezone from moment. However this was confusing as it would appear you have that timezone saved in the DB when you really didn't. Now we do not autofill the dropdown and added a button to automatically guess the current timezone to make everything more explicit.
Based on reports here https://meta.discourse.org/t/improved-bookmarks-with-reminders/144542
* Because the `userHasTimezone` property was computed and we were checking on an (essentially) global object, ember was not aware that the user timezone had changed because it changed in a different place. instead set the timezone as internal state for the modal on show and base the computed property off of that so it mutates correctly
* The tap-tile components were in the admin folder completely unnecessarily, move them out into the main discourse folder otherwise noone else can use the new bookmarks (icon + text is missing)
* Cosmetic fixes for the bookmark modal
* Do not show "later today" when the later time will be > 5pm
* When a custom reminder time is selected, store it in localStorage. The next time the modal is opened, if the last datetime is > now, then a new tile with "Last" will be shown that lets the user reselect that same time.
* Also add an explicit "No Reminder" option that is selected by default
Add enable_bookmark_at_desktop_reminders site setting default to false a new hidden site setting to hide the "At Desktop" reminder option so we can restrict this further until it is polished.
