Fix README Remark violations.

Author: Potherca

README.md

@@ -21,7 +21,7 @@ _Note: This plugin is compatible with both version 2.x and 3.x of_ [PHP_CodeSnif
 
 ## Usage
 
-Installation can be done with [composer], by requiring this package as a development dependency:
+Installation can be done with [Composer][composer], by requiring this package as a development dependency:
 
 ```bash
 composer require --dev dealerdirect/phpcodesniffer-composer-installer
@@ -234,10 +234,9 @@ THE SOFTWARE.
 [composer]: https://getcomposer.org/
 [contributing-guidelines]: CONTRIBUTING.md
 [contributors]: https://github.com/Dealerdirect/phpcodesniffer-composer-installer/graphs/contributors
-[dealerdirectcom]: http://www.dealerdirect.com/en
 [definition-ci]: https://en.wikipedia.org/wiki/Continuous_integration
 [frenck]: https://github.com/frenck
-[get-in-touch]: https://www.dealerdirect.com/en/contact
+[license-shield]: https://img.shields.io/github/license/dealerdirect/phpcodesniffer-composer-installer.svg
 [last-updated-shield]: https://img.shields.io/github/last-commit/Dealerdirect/phpcodesniffer-composer-installer.svg
 [license-shield]: https://img.shields.io/github/license/dealerdirect/phpcodesniffer-composer-installer.svg
 [packagist-shield]: https://img.shields.io/packagist/dt/dealerdirect/phpcodesniffer-composer-installer.svg
@@ -251,4 +250,3 @@ THE SOFTWARE.
 [travis]: https://travis-ci.org/Dealerdirect/phpcodesniffer-composer-installer
 [tutorial]: https://github.com/squizlabs/PHP_CodeSniffer/wiki/Coding-Standard-Tutorial
 [using-composer-plugins]: https://getcomposer.org/doc/articles/plugins.md#using-plugins
-[vacancies]: https://www.dealerdirect.com/en/vacancies