+define arbitrary actions for commands like "update", "checkout", or "commit".
+
+B<mr> cds into and operates on all registered repsitories at or below your
+working directory. Or, if you are in a subdirectory of a repository that
+contains no other registered repositories, it will stay in that directory,
+and work on only that repository,
+
+The predefined commands should be fairly familiar to users of any revision
+control system:
+
+=over 4
+
+=item checkout (or co)
+
+Checks out any repositories that are not already checked out.
+
+=item update
+
+Updates each repository from its configured remote repository.
+
+If a repository isn't checked out yet, it will first check it out.
+
+=item status
+
+Displays a status report for each repository, showing what
+uncommitted changes are present in the repository.
+
+=item commit (or ci)
+
+Commits changes to each repository. (By default, changes are pushed to the
+remote repository too, when using distributed systems like git.)
+
+The optional -m parameter allows specifying a commit message.
+
+=item diff
+
+Show a diff of uncommitted changes.
+
+=item log
+
+Show the commit log.
+
+=item list (or ls)
+
+List the repositories that mr will act on.
+
+=item register
+
+Register an existing repository in the mrconfig file. By default, the
+epository in the current directory is registered, or you can specify a
+directory to register.
+
+=item config
+
+Adds, modifies, removed, or prints a value from the mrconfig file. The next
+parameter is the name of the section the value is in. To add or modify a
+value, follow it by one or more instances of "parameter=value". Use
+"parameter=" to remove a parameter. Use just "parameter" to get the value
+of a parameter.
+
+For example, to add (or edit) a repository in src/foo:
+
+ mr config src/foo checkout="svn co svn://example.com/foo/trunk foo"
+
+=item help
+
+Displays this help.
+
+=back
+
+Actions can be abbreviated to any unambiguous subsctring, so
+"mr st" is equivilant to "mr status", and "mr up" is equivilant to "mr
+update"
+
+Additional parameters can be passed to most commands, and are passed on
+unchanged to the underlying revision control system. This is mostly useful
+if the repositories mr will act on all use the same revision control
+system.