provision/docker/docker,provisioner: changing return args order of runCmd

And using : to assign to error (maybe a merge failure...)
provision/docker/provisioner.go: using mixedCaps instead of underscores
provision/docker/provisioner_test.go: uncommenting, fixing and spliting Provision test
etc/lxc: user-registration enableb by default.
docs/lxc: update ubuntu version.t
provision/local: logging the combined output from cmds.
provision/docker,provision/local: using different mongo collections

This fixes any races conditions
provision/docker/docker.go: using mixedCase instead of underscores and removing named returns
provision/docker/docker.go: fixing undefined variable assignment
provision/local: added method to wait an specific container state.

Related to #398.
provison/local: using waitUntil before setup.

Closes #398.
cmd/tsuru-base: use local time on log output
cmd/tsuru-base: make log tests more reliable

We don't want these tests breaking on different time zones :)
cmd/tsuru: version 0.7.7
provision/local: waiting the network is up before run the setup.

Related to #398.
renamed local provisoner to lxc.
renamed local to lxc.
testing: added fake implementation of a SMTP server

This fake smtp server is handy for tests. Whenever a new message
arrives, it stores it in the MailBox slice, so testers can check for
messages in this slice.
testing/smtp: add some docs
testing: added method to reset SMTPServer