Just reset the freenas:state for the last snapshot sent.

In theory freenas sends all snapshots incrementally, thus all snapshots
will have that flag reset, no need for recursive removal. That was too
slow in our setup.
Cleaner log message if replication failed
Revert "Tactical improvement for defect #3794 to reduced zfs inherit on remote system to just the last snapshot vs entire dataset"
in favor of a better fix.

This reverts commit 2ab187ec3f27208c028262d48a2e7f5054dbb47d.
Merge branch 'master' of https://github.com/rkojedzinszky/freenas into rkojedzinszky-master