Apartments lab

Overall enjoyed this assignment- good practice with inheritance and using blocks, procs to iterate over data structures.  I wasn't quite sure what you meant for the tenants and apartments array actually being prevented from being modified directly.  I used a getter method to access tenants in the building superclass, so you could change it by shoveling on items, but you couldnt change it from being an array to another data type.  Is there some other way to hide it more?  I looked into protected methods but these are only accessible to sublasses, and I needed to acccess the tenants in the superclass.  Also was trying to figure out how to get the average credit rating of the apartment without typing out the whole if/else structure again, but couldn't think of a way to do this.  Will ask about these tomorrow if we don't go over it.