tree 24e3b4aeb23578b483b46f9804d0a6545aac5a8b
parent ee0c74b77a24dc4fdaad2c950bcf621b6fa54095
author Jason Evans <jasone@canonware.com> 1476162910 -0700
committer Jason Evans <jasone@canonware.com> 1476162910 -0700

Do not advance decay epoch when time goes backwards.

Instead, move the epoch backward in time.  Additionally, add
nstime_monotonic() and use it in debug builds to assert that time only
goes backward if nstime_update() is using a non-monotonic time source.