struct KeyMapNode * OpenKeymap(
STRPTR name );
name - Keymap name. Can be a full pathname or just a name.
In the latter case DEVS:Keymaps is assumed to be a
path to the file.
A pointer to the loaded keymap.
This function automatically keeps track of loaded keymaps
via keymap.resource. No more than a single copy of the keymap
will be loaded.