Make the ready overlay blink. Fixes #3032.
Issue #4650: Abort Mission Confirmation

Adapted the confirmation dialog from the CnC mod and wired it to
the "Abort" and "Surrender" buttons.
Merge pull request #5178 from pchote/get-blinkin-ready

Make the ready overlay blink.
Add confirmation-dialogs.yaml to d2k's and ts's mod.yaml or they crash
Hide ingame menu before showing the confirmation dialog

As a bonus, don't show the confirmation dialog if the game is over.
Update license headers
Merge pull request #5180 from pavlos256/abort-mission-confirmation

Closes #4650