Acquire mode is supported on KAME now, remove caveat.
Basically, a rote copying from markus@ work on OpenBSD-HEAD, but removed
openbsd-specific locks and replaced sysctl(KERN_ARND) by _rs_random_buf()
loopback call.
Placing configuration opts back
Removing $OpenBSD$
moving check for stir from _rs_random_buf() to arc4random_buf(), since we use _rs_random_buf() also from _rs_stir()
Run a timer to flush the SADB after power resume on Apple
Merge https://github.com/andreldoliveira/openiked