Add 'link' option to skip loglevel and module info in output

[izikeros]

Skip the level and module name to have log line starting with message. This option affects also how the "block" and "module" violations are printed - the path is in the front of the message. When using xenon in PyCharm terminal, one can benefit from PyCharm changing the path to the violation location into the active link.

For more details see Feature Request #49