Add regions to empty classes.

I added region declarations to the empty classes in Model, View, and
Control. The region statements are as follows:

static	- static variables and methods
fields	- private/protected instance variables
properties  -  public instance variables and accessors to private fields
constructor - constructor(s) for the class
methods - instance methods (static methods should be in the static region)

These statements don't actually affect the compiled code, but they improve
clarity and organization and allow easy code folding, so you can focus on
just the parts of the code that you need to. Please put your code inside
of the appropriate region.

Note: Many classes may not have any static members or methods- in this
case, you can leave this region blank.
Also, note that the fields region is reserved for private/protected
attributes whereas the properties region should be used for public
attributes or properties that expose private fields (Properties are C#'s
version of Java's get/set accessors)