Add the class keyword "traits" to the LowercaseClassKeywordSniff

Fixes #6
Add a sniff to check for the correct file extension

Fixes #7
Checkstyle Fix
Adjust the repository url
First version

* Checks if the filename is the same as the classname
Ignore OSX files
Checks all rules

* Filename has to be UpperCamelCase
* Files that contain Interfaces must have the file name end on "Interface"
* Raise a warning if a file don't contain a class or an interface
[FEATURE] #50200: Add a sniff for the new filename scheme
Merge branch 'FilenameSniff' into develop
[BUGFIX] #42288: Underscores are allowed in function name

Add an exception for user_ functions.
Working draft. Need some cleanup.
Add a check for Switch control structures.

Fixes #10124, #10125, #10126, #10127
ConcatenationSpacingSniff could check for too many spaces

* added a warning if there are more than one spaces around concatenation operators.
* add sniff documentation
* updated documentation.html

Fixes #41156
CGL Clean-up
Closing braces of a scope have to be on his own line and aligned correctly

Fixes #10133
Dont use nested "ternary conditional" operators

Fixes #10123
Remove the requirement of custom installer
Make ruleset installable into composer project by using simplyadmire/composer-plugins
Prepare PEAR release
Add the pear package