match statement and byte

[Akuli]

Currently match some_byte: doesn't work, but match some_byte with bytecmp does, where bytecmp is the following function:

# TODO: should not be needed
def bytecmp(a: byte, b: byte) -> int:
    return (a as int) - (b as int)

In fact, the match statement only works with enums if you don't use match ... with syntax.

Discovered in #699