Hy 1142 rectangle class

Spawned from https://github.com/WebFilings/wf-js-viewer/pull/167


**Jira Ticket:** [HY-1142](https://jira.webfilings.com/browse/HY-1142)

## Problem
Want a simple rectangle class to support hit testing forbidden areas.

## Solution
Created a new Rectangle class that includes a single method to determine if a point is inside the rectangle.

## How to QA/+10
1. CI Build Passes
1. Check out the `HY-1142_rectangle_class` branch
1. Run `./init.sh && grunt qa`
1. Confirm lint and unit tests pass

# Code Review             
@timmccall-wf @lancefisher-wf @robbecker-wf @patkujawa-wf @georgelesica-wf 
For shapes it's possible that it intersects the Rectangle but is not contained by it. This method does the correct thing that its name implies, that the shape is completely contained by the rectangle.
Just rambling here, I guess we could always add intersects() later.