Add support for 'name' and 'use' which allows more of the latest magic
files to work unchanged. (We are still missing 'indirect' and a few
other bits.)

New implementation of the file(1) utility. This is a simplified,
modernised version with a nearly complete magic(5) parser but omits some
of the complex builtin tests (notably ELF) and has a reduced set of
options.

ok deraadt