Merge branch 'master' into stable

Mark as RC

Update CHANGELOG for v1.2.1

Merge in revno change for 1.2.1

Merge branch 'master' into stable

Conflicts:
	CMakeLists.txt
	src/zopt.ggo

Merge branch 'stable' of github.com:zmap/zmap into stable

Bump revno to 1.2.0-RC3

Bump revision number to 1.2.0-RC2

Always add 0.0.0.0 to a blacklist

This is now required, because 0 is used a flag value meaning "stop" in
shard_get_next_ip().