download URL updates for master
Merge branch 'dev'
Version bumps and NEWS update for the 1.8.0 release
Bugfix: Bad shift value in extmon pipe comms code.

Shifted a value by 8 too many bits.  Instances with less than
256 specific extmon commands would not have been affected, but
those with >= 256 would have experienced early startup failure
when initializing extmon communications.
Fix unaligned access issues

Note this relies on gcc __attribute__((__packed__)), which some
  non-gcc compilers also support.  Probably ok, could dive deeper
  on supporting other compilers if anyone ever files a bug.
unaligned access fixup
minor comment/style cleanup on prev two commits
Switch version policy to SemVer