Replace usages of SplitBoxResult with option types
Flatten some pattern matching
Add ref test for nested inline elements
Avoid splitting boxes if possible
Add doc comments explaining some return types
Pass external dependencies to submodule Makefiles

Part of the fix for #2137.
Do not log CSS parse errors to stderr by default.

Fix #2083. Change the log level of CSS errors from error to info.
Remove a workaround for a Rust bug.

We’ve upgraded to a Rust version that fixed mozilla/rust#13322.
Optimize CSS error logging: check log level before task-local silencing.
Add some fmt::show implementations to make debugging layout easier.
Make ComputedStyle fields private and add getters.

This isolates layout code from upcoming refactoring in properties.rs.mako.
Un-disable and fix some warnings in the style crate.
Remove CowArc and use the new Arc::make_unique() method instead.
Remove *() hack now that rust upgrade is complete. Fixes memory corruption bug #2412.
Replace deprecated rev_iter() by iter().rev().
Implement CustomEvent (#2173)
auto merge of #2374 : Manishearth/servo/customevent, r=jdm

This was previously PR'd on #2218
auto merge of #2468 : glennw/servo/show-traits, r=jdm
auto merge of #2471 : bjz/servo/split-to-width, r=pcwalton

@pcwalton r?
Remove the workaround for Rust issue 10683.