Removes the logic to search for a distro release version based on the --dist
argument and instead makes this as required parameter provided by the
user, reducing code size considerably as the expense of letting the user
responsibility to define it. The --dist argument was also used as branch
name in some cases (where --dist was not defined) so this change splits the
original parameter semantic in two: one for defining the distro release
version (--dist) and another to define the branch name (--branch). Finally, a
short README with single scenario as example.
Signed-off-by: Leo Sandoval <lsandova@redhat.com>
