More accurate margin collapsing
Implement the rest of 'text-decoration' property.
Introduce a createText function.
Issue #852 - Implement the Node.textContent setter.
Fix android/font.rs. Add an issue in macos/font.rs
Fix error: declare a module.
auto merge of #932 : june0cho/servo/text_deco, r=metajack

Implement 'overline' and 'line-through' in 'text-decoration' property. Add a test case.
Pass the AbstractNode into the Node.textContent setter.
Make all DOM manipulation wait until it's safe to do so (ie. all reflows for the page have completed). Fix a race where a newly-initiated reflow would be considered complete when receiving the completion notice for the previous reflow.
Add a test for Node.textContent.
auto merge of #947 : jdm/servo/textcontent-setter2, r=metajack
auto merge of #903 : ILyoan/servo/margin_collapse_fix, r=metajack
Add large matrix multiplication demo.
auto merge of #950 : jdm/servo/matrixmath, r=metajack
Change retrieval of buffers from sublayers to both clip relative
to the scrolled position of its parent layer and to offset the
origin, since each layer assumes that its origin is 0,0.
auto merge of #944 : larsbergstrom/servo/iframe_display, r=pcwalton

The quadtree was checking to see if a window's position was within the clip region before drawing it. However, the window's position is in page-relative coordinates whereas the clip region is in window-relative coordinates. So, unless the iframe happened to fall in the clip range, it would never have tiles returned.

If an iframe had enough content that it spilled outside of its clip range, different logic was triggered that would cause it to receive a ReRenderMsg anyway, which circumvented all of this.

@eschweic, can you please review this if you have a minute? I believe that I've correctly captured the four checks we want to make (two each for ```x``` and ```y``` directions to determine if the window is in or out, but I'd appreciate another set of eyes on it.

For some example data, in a call to ```get_tile_rects``` for an iframe that is sized to 400x400 and is 428-ish pixels down the page, with a browser frame that is 600 total pixels tall, that function is called with:
window origin geom::point::Point2D<f32>{x: 9f32, y: 428.6000061f32}
window size geom::size::Size2D<f32>{width: 400f32, height: 171.3999939f32}
self origin geom::point::Point2D<f32>{x: 0f32, y: 0f32}
self size 512f32" 
clip: size::Size2D<f32>{width: 400f32, height: 400f32}
configure: Control Skia debugging with a separate --enable-debug-skia

Fixes #921.
auto merge of #951 : kmcallister/servo/debug-skia, r=metajack

Fixes #921.
Implement document.getElementById().