LM hash support for OCLHC

[chort]

Here's how I'd like LM to work:

- Accepts 16char or 32char hash
- Outputs the plain for each independently, even in outfile (i.e. the hash length in outfile is 16char)
- Can reassemble whole plain with --show
- Crack right hash first, because in nearly every case it will be faster than the left hash (and will probably give clues about the left half)

- Optionally break masks > 8 and apply to each half in the order given (i.e. ?l?l?l?l?l?l?l?d?d?d would become <left>?l?l?l?l?l?l?l <right>?d?d?d)
- Alternatively, display error for masks longer than 7