Mark all on `% m RET`

[pennersr]

In other parts of Emacs, Dired for example, I can type % m RET to mark all files.

However, when I try to do the same on a package using tablist, for example Silex/docker.el: entering M-x docker-containers RET % m RET results in an error message: No regexp given.

Please consider altering the behavior to make the user experience consistent to that of default Emacs and select all entries when no regexp is given.