changed Rover initialization

* added orientation
* x coordinate, y coordinate, and orientation are received as a HashMap
* adjusted tests accordingly
created a method to extract rover initial position data

* it turns "1 2 E" into a HashMap
  * "xCoordinate" = "1"
  * "yCoordinate" = "2"
  * "orientation" = "E"
allow Printer class to show 2d String arrays
made Rover store x and y coordinates as Integers

* changed from String to Integer to streamline app controller's interactions with Grid
grid can now properly place rovers

* created the placeRover method
* accepts a Rover and an argument
* included tests to ensure proper functionality!

Note: the grid's (0,0) location is the bottom left, which is what people generally expect
instances of Rover can move forward in any direction

* changed orientation from a String to a char
* done so that it works with switch statement
* tests are included for Rover moving forward for N, S, E, W
rovers are able to turn right

* leads to change in orientation

ex:
  * North becomes East
  * East becomes South
rovers can now turn left

    * leads to change in orientation

    ex:
      * North becomes West
      * West becomes South
rover is able to execute a series of commands!

* whoo hoo! dance all day!
renamed Grid's createBody method

* renamed it to be fillWithDefault
* name is more descriptive and more accurate
AppController completes app functionality, see details:

* exposes a run method which executes the proper sequence of commands
  * uses TxtReader to read txt file
  * uses Parser to extract grid data and rover data
  * creates Grid and then Rovers
  * places Rovers on Grid
  * gives commands to Rovers
    * Rovers execute the commands
* BOOM, tests were already included for every class mentioned!
created AppInterface show user the app progress

* created a ContextPrinter to elaborate to user about the app's execution details
* used a series of print statements and thread sleeps
removed AppController's main method

* made it so that there is only one main method within the whole package
* main method is in AppInterface
updated README