Stop checking if ri->address is an IP

since router_parse_entry_from_string() already checks whether
!tor_inet_aton(router->address, &in)

(And no need to print address, since router_describe does that.)
stop passing "address" around the directory_initiate_command* funcs

since it was always just the string version of "addr" anyway
use router->addr for log messages and controller events

(rather than router->address)
use me->addr when adding our address to our exit policy

(rather than me->address)
stop setting, or using, router->address

resolves ticket 5528.
Merge remote-tracking branch 'arma/ticket5528'

Conflicts:
	src/or/router.c
	src/test/test_dir.c