Checkin Timer

[bgraves49]

Checkin Timer: Have another tab to set during events or calls that will track the time someone is on the call and alert you (on your set variable) to checkin with them. In other words, pretty much a timer you can set and then click a single button to reset it and then logs of the checkin times.

Have option for user to reset their own tracker/timer as well from their app.

This is best to work on the phone app as well to allow for mobile usage.

[ucswift]

Being added into the system in PR #312. Changes that require app updates; Unit and Responder apps for Checkin's and Dispatch for timer monitoring and notifications, will be later.