Basic hit testing functionality
Update rust-css and rust-netsurfcss
Add horizontal borders, margins and padding. Broken until rust-css supports padding
Fix method names and dynamic borrow check failures
Refactor a bit and compute vertical margins as well.
Update rust-css and fix some dynamic borrow check failures
Add comments and compute heights properly
Update border rendering
mouse event handling

Conflicts:
	src/support/geom/rust-geom
more mouse events
rust-glut static vars for mouse buttons
adding more mouse events
glut static vars
handle mouse_up, mouse_down, and click separately; pass specific button to script_task
Rename `with_imm_base` to `with_base`.
Merge branch 'master' of git://github.com/pcwalton/servo
improved profiling metrics