Made 140 the default unitWidth as other files used 140 as default
Fixed a bug where pageRegionWidth was set to "auto" and we tried to parse it as an int resulting in NaN and breaking the layout
Checked first parent for unitWidth in tileBindings.js and added a default unitWidth of 140--although this isn't really a solution because sometimes there is no parent and we get an error because we try to get unitWidth of undefined
Checked if tiles was defined in the afterRender function in tiles.js