Re-enable Google Analytics
Undo the last checkin for templates/base.html. It was local for testing
so GA wasn't hit every time.
Generate Obstructions
Obstructions are created on the board and are represented by black boxes.
The underlying cell objects are updated from just a count to a count and
a blocked value.
The number of obstructions generated is random based on a probablility
distribution. The size of each individual obstruction is also random, again
based on a probability distribution.