Nuke src/cairo, src/pixman, and src/rust-cairo
Nuke Cairo
Update submodules
gfx: Refactor the Mac platform goop into platform/
Refactor the Linux font stuff
Add license headers
Merge pull request #335 from brson/license

Add license headers
Merge pull request #334 from pcwalton/nuke-cairo

Nuke cairo
Remove native.rs. It's no longer needed; just use platform::* directly.
Remove some module aliases.

These aliases were there for old versions of resolve, and are no longer needed.
Refactor glyph.rs to modern Rust coding style
Refactor the HarfBuzz shaper to be in line with modern Rust style
Rename one of the two modules called "shaper"
Hoist all `extern mod` directives to the top level

This improves compile time and makes `use` directives look cleaner.
Nuke the TGA encoder
Adding config.tmp to the ignore list

In case the ../configure script fails or the user cancels it, the temporary file
generated is shown as "untracked file" when running "git status". 

Adding it to the ignore file.

Fixes #341
Merge pull request #342 from vivekgalatage/master

#341: Add config.tmp to the git ingore list
Modifying submodules to use https instead of git for git URL

Currently submodules are using the git protocol. Git protocol is blocked
by certain corporate networks which makes it difficult to sync the submodules.

Replacing the git protocol with https in order to sync the submodules.

Fixes #333.
Merge pull request #350 from vivekgalatage/master

Support for https:// protocol for git submodules for servo
Do not assume python is an interpreter for Python 2

On some distributions and configurations, the python command might refer to
python3 instead of python2, breaking the build. Fix this by using the first of
python2, python2.7, or python.