Complete app name for log.
add other log flags to zsh completion
use new heroku-go for orgs fixes, simplify transfers w/ orgs
access listing for org apps
use orgs paths for access-add + access-remove
better zsh copmletion for access-add
better org-checking funcs
reorder mustGetDBInfoAndAddonMap API call for optimal concurrency
default to primary database in pg-info

If user doesn't provide a database name for pg-info, we will instead
default to whichever postgres addon  matches their DATABASE_URL. Looking
up info on your default database is very common, and this makes that
much easier.

Fixes #155. /cc @will