Added Prison

Adds a guaranteed single spawn 3x3 prison with basement.  This also includes basic structure and logic for the new bar doors.  So, bar doors are transparent, non-bashable, regular difficulty to pick, and nearly as hard as popping a man hole cover off to pry open with a crowbar.  They also have the interesting feature of locking as soon as you close them.  They are great in that sense to hold off normal zombies with but there isn't a reliable way to open them so it is also very easy to get trapped.  To enter the basic prison, grab a car and hit 70 while plowing straight through the center of the driveway.  With some luck you will be able to pierce the command desk cage at the center of the building.  From there there is a set of stairs in the library to the dining facility below.  Expect the difficulty to rise as I get a better feel for how dangerous it should be to explore.

Soon to be added are the two quests that use the building:
vigilante 5 - recovering the execution records to see where all of the prisoners are disappearing to...
martyr 4- investigating a visionary that is on death row that the priest's journal alludes to

[Spoiler]  Without a high mechanics skill or strength you can also melt the bars away with concentrated acid :D