Impelemented zooming and slightly better scrolling.
Merge with pcwalton's updated branch
Changed texturing mode to LINEAR for better zooming
Add initial support for the line-height property. Line height is only based on the tallest box in each line and does not factor in the vertical-alignment. Improves whitespace handling by passing the whitespace state between function invocations.
auto merge of #515 : pcwalton/servo/master, r=metajack

Changes authored by me have not yet been reviewed; the other changes have.

r? @metajack
Update ignores for new bindings path.
Fix makefile targets.
Fix dependencies.
Get rid of initial reshape.
Switch to GPU rendering.

This uses shared GL contexts and FBO rendered textures.
Update submodules.
Merge onto mozilla/servo master
auto merge of #518 : metajack/servo/gpu-rendering, r=pcwalton

This uses Skia GL to render to offscreen FBOs and then passes the resulting textures directly to the compositor.

It depends on https://github.com/mozilla-servo/rust-azure/pull/26 and https://github.com/mozilla-servo/skia/pull/14

r? @pcwalton
Merge branch 'master' of https://github.com/mozilla/servo
decouple script from compositor
communicate via layout
refactor channel wrappers from *Task --> *Chan

fix merge fallout
fixed docstring for create_compositor_task
*Chan.send() convenience functions
profiler refactor to print every period if new data has arrived
Add initial support for the line-height property. Line height is only based on the tallest box in each line and does not factor in the vertical-alignment. Improves whitespace handling by passing the whitespace state between function invocations.
refactor compositor interfaces \--> RenderListener + ScriptListener; AttachCompositorMsg added to render_task::Msg

updated to reflect comments