Add Initialise Boundary Code

After the Google Map has been initialised, display the starting
boundary. This marks the edges of our grid.
Add Output Div to Tester.html

Create a div on our testing page where to insert outputted text
Add 'Create Grid' Button to Test Page

Assigned create grid action when our ‘button’ on the test page is
clicked.
Add Initialise Grid Functionality

Added grid initialisation functionality to the module. This consists of
two private functions:

_calculateGrid works out how many grid boxes we need to create and what
size each box is going to be

_initializeGrid creates all our grid boxes (Google Maps rectangle
objects)
Add 'Updated' Custom Event & Ongoing Fixes

Added window event triggered when Grid has been updated. This can be
used to delay actions until after the grid has been created (or
changed).

Renamed:

‘empty’ to ‘clear’ (clearGrid)

Improved functions:

* Add Click Event to Region

Added functions:

* Clear grid (removes current rectangles)
* Get Region By Index