class used to launch ivy as a standalone tool
arguments are :
-conf
: indicates the path to the ivy configuration file
ivyconf.xml is assumed if not given
-cache : indicates the path to the cache directory
cache is assumed if not given
-ivy : indicates the path to the ivy file to use
ivy.xml is assumed if not given
-retrieve : when used, retrieve is also done using the given retrievepattern
-revision : the revision with which the module should be published, required to publish
-status : the status with which the module should be published,
release is assumed if not given
-publish : the pattern used to publish the resolved ivy file,
ivy-[revision].xml is assumed if not given