Improved Code Sniffing (#928)
* Adding strict PSR2 enforcement for new code
ci now brings in phpcs globally so it can be used by devs as well without polluting their openemr packages
* Using `composer global exec` to ensure accurate COMPOSER_HOME
* Adding lint_style_staged as an option, allowing pre-commit checks for PSR
generalized sniffing to function in ci.sh
* Fixing environment variable in .travis.yml
* Fixing multiline issue
* Allowing detection of `COMPOSER_HOME` without `composer exec`
* Actually installing phpcs on
* Removing Travis' strict interpretation of new commits