Add basic_fetch and a skeleton http_fetch
Add a basic CORS Cache and a CORS Cache trait
Add a task-based CORS Cache
Update MANIFEST.json to current web-platform-tests.

This was forgotten in the last update. The README is also updated as a
reminder for future updates.
Some docs
Merge pull request #3169 from Ms2ger/update-manifest

Update MANIFEST.json to current web-platform-tests; r=jdm
Use macro getters for input elements
Introduce the NativePropertyHooks struct.

This will be required for the cross-origin wrapper work.
Merge pull request #3176 from Manishearth/more-macros

Use macro getters for input elements: r=Ms2ger
Merge pull request #3175 from Ms2ger/propertyhooks

Introduce the NativePropertyHooks struct; r=jdm
Transmute std::raw::TraitObject rather than (some) custom tuples/structs.

Context:
http://www.mail-archive.com/dev-servo@lists.mozilla.org/msg00867.html

This fixes the known issues, but there might be other places
where we do "bad" transmutes that I haven’t discovered.
Add a canvas create, break script’s dependency on gfx.

The build time on my laptop after touching gfx goes from 1m37s ot 46s.
Introduce ConstantSpec::get_value.

I'll need it for cross-origin wrappers as well.
Merge pull request #3177 from Ms2ger/ConstantSpec

Introduce ConstantSpec::get_value; r=jdm
Uppercase element.tagName for HTML elements only

Fixes #3146
Merge pull request #3147 from mbrubeck/tagname-upper

Uppercase element.tagName for HTML elements only r=Ms2ger
Merge pull request #3170 from SimonSapin/trait-object-transmute

Transmute std::raw::TraitObject rather than (some) custom tuples/structs
Support callback return types in codegen
Merge pull request #3141 from Manishearth/fetch-stuff

Some more Fetch and CORS Cache stuff; r=jdm
Merge pull request #3178 from SimonSapin/canvas-crate

Add a canvas create, break script’s dependency on gfx.