This PR:
Keeps track of time spent in mission
Introduces a new "turnless mode" setting, which activates the following:
- At the end of a mission, fast forwards through the time spent in the
mission, skipping any combat (which has already been tracked through
state.json)
- Removes killed flights from the ATO
- Does not start a new turn, instead allows the player to continue the
current turn.
d09a15a7f3
