NPC Schedules need a rework

[BramvdnHeuvel]

Currently, gen/house/schedule/__init__.py gives people their schedule. However, the file is currently quite a mess, and people have requested for nightly schedules for the guards, so that there will always be a guard awake in the town.

Make sure that you do not pass any objects like House, Person, Neighbourhood or Village into the function, but that you gather all relevant information before you pass them into the function. The reason for this, is that some of the inputs may not have been generated either, and they use a seed of their own as well. If you gather them in the function, they might overwrite the seed that you're using to generate the schedules, and you might generate a different schedule.

Acceptation criteria:

• There is a chance that an NPC has a nightly schedule;
• The file gen/house/schedule/__init__.py has been refactored and is now more readable.

Please submit your code in a pull request.