of "local" it will not mount filesystem types it identifies as
network file systems (currently just nfs). Call the function twice,
before networking starts with arg "local", after networking starts
with arg "network". Remove critfs_require_network as is now redundant.
switch and a set of flags. Get rid of DEFAULT flags entirely. Print
warnings if on/off switches are not set, or are set incorrectly.
Add a shell function to simplify this on/off switch testing.