CVE-2017-13000/IEEE 802.15.4: Add more bounds checks.

While we're at it, add a bunch of macros for the frame control field's
subfields, have the reserved frame types show the frame type value, use
the same code path for processing source and destination addresses
regardless of whether -v was specified (just leave out the addresses in
non-verbose mode), and return the header length in all cases.

This fixes a buffer over-read discovered by Forcepoint's security
researchers Otto Airamo & Antti Levomäki.

Add tests using the capture files supplied by the reporter(s).