t_netfail: synchronization routines to detect failover/respawn
t_netfail: synchronization routines to detect failover/respawn

These are not strictly accurate per se, but will allow waiting for a
specified amount of time, checking that the failover/respawn has been
properly performed.

Change-Id: I4010cbc699f6a7442a94f0b4f37359b5f856daf8
Reviewed-on: http://review.couchbase.org/48270
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Subhashni Balakrishnan <7129c8e37b832c7bd362ff375532d24b98ef5162@gmail.com>

kojiromike/libcouchbase,mody/libcouchbase,PureSwift/libcouchbase,PureSwift/libcouchbase,mody/libcouchbase,couchbase/libcouchbase,avsej/libcouchbase,signmotion/libcouchbase,mody/libcouchbase,mody/libcouchbase,senthilkumaranb/libcouchbase,avsej/libcouchbase,kojiromike/libcouchbase,couchbase/libcouchbase,couchbase/libcouchbase,maxim-ky/libcouchbase,maxim-ky/libcouchbase,couchbase/libcouchbase,PureSwift/libcouchbase,couchbase/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,avsej/libcouchbase,signmotion/libcouchbase,senthilkumaranb/libcouchbase,signmotion/libcouchbase,avsej/libcouchbase,PureSwift/libcouchbase,couchbase/libcouchbase,couchbase/libcouchbase,signmotion/libcouchbase,kojiromike/libcouchbase,kojiromike/libcouchbase,maxim-ky/libcouchbase,avsej/libcouchbase,senthilkumaranb/libcouchbase,maxim-ky/libcouchbase,senthilkumaranb/libcouchbase