Break out the contributing notes into CONTRIBUTING.md

Author: dwijnand

CONTRIBUTING.md

@@ -0,0 +1,30 @@
+# Contributing to rustup
+
+1. Fork it!
+2. Create your feature branch: `git checkout -b my-new-feature`
+3. Commit your changes: `git commit -am 'Add some feature'`
+4. Push to the branch: `git push origin my-new-feature`
+5. Submit a pull request :D
+
+For developing on `rustup` itself, you may want to install into a temporary
+directory, with a series of commands similar to this:
+
+```bash
+$ cargo build
+$ mkdir home
+$ RUSTUP_HOME=home CARGO_HOME=home target/debug/rustup-init --no-modify-path -y
+```
+
+You can then try out `rustup` with your changes by running `home/bin/rustup`, without
+affecting any existing installation. Remember to keep those two environment variables
+set when running your compiled `rustup-init` or the toolchains it installs, but _unset_
+when rebuilding `rustup` itself.
+
+We use `rustfmt` to keep our codebase consistently formatted.  Please ensure that
+you have correctly formatted your code (most editors will do this automatically
+when saving) or it may not pass the CI tests.
+
+Unless you explicitly state otherwise, any contribution intentionally
+submitted for inclusion in the work by you, as defined in the
+Apache-2.0 license, shall be dual licensed as in the README, without any
+additional terms or conditions.

README.md

@@ -32,7 +32,7 @@ And it runs on all platforms Rust supports, including Windows.
 * [Security](#security)
 * [FAQ](#faq)
 * [License](#license)
-* [Contributing](#contributing)
+* [Contributing](CONTRIBUTING.md)
 
 ## Installation
 
@@ -706,37 +706,6 @@ Licensed under either of
 
 at your option.
 
-## Contributing
-
-1. Fork it!
-2. Create your feature branch: `git checkout -b my-new-feature`
-3. Commit your changes: `git commit -am 'Add some feature'`
-4. Push to the branch: `git push origin my-new-feature`
-5. Submit a pull request :D
-
-For developing on `rustup` itself, you may want to install into a temporary
-directory, with a series of commands similar to this:
-
-```bash
-$ cargo build
-$ mkdir home
-$ RUSTUP_HOME=home CARGO_HOME=home target/debug/rustup-init --no-modify-path -y
-```
-
-You can then try out `rustup` with your changes by running `home/bin/rustup`, without
-affecting any existing installation. Remember to keep those two environment variables
-set when running your compiled `rustup-init` or the toolchains it installs, but _unset_
-when rebuilding `rustup` itself.
-
-We use `rustfmt` to keep our codebase consistently formatted.  Please ensure that
-you have correctly formatted your code (most editors will do this automatically
-when saving) or it may not pass the CI tests.
-
-Unless you explicitly state otherwise, any contribution intentionally
-submitted for inclusion in the work by you, as defined in the
-Apache-2.0 license, shall be dual licensed as above, without any
-additional terms or conditions.
-
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