Replace loopback url (localhost, etc) with network bridge ip. Bug 1309207.
state: strictLocalID tweaks

1. Return an error instead of a flag to reduce boilerplate at call
sites.

2. Use strictLocalID in more places where appropriate.
Replace loopback url (localhost, etc) with network bridge ip. Bug 1309207.
Merge remote-tracking branch 'origin/replace-localhost-in-proxies' into replace-localhost-in-proxies

Conflicts:
	environs/config/config.go
Resolving merge conflict.
Merge pull request #1022 from mjs/use-strictlocalid-more

state: use strictLocalID in more places where appropriate
Merge pull request #1017 from anastasiamac/replace-localhost-in-proxies

Replace loopback url (localhost, etc) with network bridge ip. Bug1309207

this changes have been done and reviewed in another branch...