Allow to use '*test*' in enablerepo for yum action

Yum commandline permit to use a wildcard to enable and disable
repositories in the --enablerepo switch, permitting to enable
a complete set of repository at once ( like all rpmfusion, all
update-testing, etc ).

However, this doesn't work in yum due to more stringent checks
that verify that a exact match is given for the name of the
repository , see commit 5c26805.

This commit enhance the check by permitting to test more than
1 repository at a time, thus permitting to use wildcards.