Update genconf.lua

following modifications/additions were made in https://github.com/brammert010/genconf.lua fork:

* added support for use of vars in target path and filename
* added support for auto-creation of target paths based on added 'paths' section to config file
* added support for configurable template path (--tplpath)
* added support for configurable config file (--config)
* disabled stop-criteria in case given var on the command-line is not known in configuration (just ignore)