ruby-install 0.4.1

### 0.4.1 / 2014-02-28

* Always clean the source directory before re-building to prevent linking
  errors.

#### functions.sh

* Added the `clean_ruby` function to handle cleaning the source directory.

#### ruby

* Added versions for 2.1.1, 2.0.0-p451 and 1.9.3-p545.
* Removed version aliases for 1.9.1 and 1.9.2.

#### jruby

* Added the 1.7.11 version.
* Copy the compiled ruby instead of moving it.

#### maglev

* Copy the compiled ruby instead of moving it.

#### mruby

* Add support for building with `-j,--jobs`.
* Copy the compiled ruby instead of moving it.