Logger class, sensorCount get methods, UI changes

Changes:

- Number based menu with more options + exit function
- public getSensorCount method in Room.java
- UI cleanup in SquareSensor.java
- Completed Logger class

Required:

-Error checking (overlapping sensors, sensors larger than room, sensor
dimension input)
Merge pull request #1 from v3rso/master

Logger class, sensorCount get method, UI changes