This patch updates the documentation to match the actual behavior, and
adds a configuration option to remove the leading prefix.
The extra wildcard is causing problems when there are two variants in
the compose and one UID is a suffix of the other (e.g. DevTools and
Tools), since multiple files will match the shorter name and an error
will be reported.
JIRA: RHELCMP-1086
Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>