Sometimes building with openssl requires major intervention of pointing the include path to the local installation of openssl, when the brew link refuses to link.
- [ X] `./mach build -d` does not report any errors
- [ X] `./mach test-tidy` does not report any errors
- [ X] These changes do not require tests because it’s a documentation change
Backspace and Shift-Backspace are no longer used to go
backwards and forwards through history.
Instead, Alt+Left Arrow and Alt+Right Arrow are used now.
Without this package, I get this error:
```
Compiling servo-freetype-sys v2.4.11
Build failed, waiting for other jobs to finish...
error: failed to run custom build command for `dbus v0.3.3`
Process didn't exit successfully: `/dsk/src/servo/target/release/build/dbus-7f7af798babde0c1/build-script-build` (exit code: 101)
--- stderr
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: "Failed to run `\"pkg-config\" \"--libs\" \"--cflags\" \"dbus-1\"`: No such file or directory (os error 2)"', ../src/libcore/result.rs:785
note: Run with `RUST_BACKTRACE=1` for a backtrace.
[Warning] Could not generate notification! Optional Python module 'dbus' is not installed.
Build completed in 0:05:27
```
It's `pacman -Su` nowadays, per https://github.com/Alexpux/MSYS2-pacman/pull/26.
(This is a very selective cherry-pick of #11392. The other parts were more controversial; they didn't fully work so let's disregard them for now.)
I feel it would make sense to make mention of this here, especially since Browser.html is part of the [road map](https://github.com/servo/servo/wiki/Roadmap) for what we aim to achieve during the year.
Change OS X 10.11 to El Capitan
I think "El Capitan" is a lot clearer than 10.11 – I had to look up which version that was. Thoughts?
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I tried to get started on Servo development but realised that a clean build of Ubuntu did not come with git out of the box. I had to manually install this before moving on with the next steps (clone and build).
In the repo title it says servo is a "parallel browser engine" whereas readme says its a "parallel browser". It will be helpful to add a more clear title.
