[Users] how to refresh REGISTER state when restarting redundant proxy

[Alan Crosswell]

We are using t_replicate() to replicate REGISTERs among redundant
proxies (and a separate presence server that needs REGISTER for
pua_bla).  Before reinventing the wheel here, I thought I'd ask if
others already have a method in place to re-sync a restarted proxy's
state?  I guess one way is to pull the usrloc data from mysql....
Another would be to somehow ask the proxy to walk the usrloc table and
do a bunch of t_registers()...

Any thoughts appreciated.
/a