Revision 1797596

[MCHECKSTYLE-337] checkstyle:check only supports xml output format, but the docs say it supports plain as well
Submitted by: Stig Rohde Døssing

Adding support for 'plain' output file format in the 'check' goal. It is still not possible to use it in combination with 'skipExec' because the plain format does not interact fully with 'violationIgnore' (which can contain fully qualified class name, when Checkstyle plain format only has the class simple name).