Streamline the travis deploy builds; when TRAVIS_TAG is set
we'll run `--release` builds.
Don't error out in fontconfig/build.rs if fontconfig is not
installed. This makes it possible to `cargo test --all` again
on the mac at the cost of potentially making it harder to troubleshoot
problems with not having fontconfig installed on linux.
However: the get-deps script is responsible for installing that.
Now that we have it running build and test, let's keep it green.
Let's take the nightly channel off; it does tend to fail and I
don't care particularly about it, and there's no need to take
up CI resources for it.
This is primarily for macos where the default freetype
installation is unable to render color emoji, but should also
help make things more consistent across the various platforms.
It's a little bit awkward on linux because the font-loader crate
pulls in the now-conflicting servo-font* crates. I've disabled
font-loader on linux systems; it's just calling fontconfig under
the covers anyway.
This removes some tricksy code in favor of a third party crate,
which unlocks the clipboard on windows. I'm not sure how well
this will work on the pure x11 impl yet.
