third_party: sync third_party/gopkg.in/yaml.v1

Update launchpad.net/goyaml to gopkg.in/yaml.v1
yaml: replace goyaml with yaml
Merge pull request #223 from crawford/yaml

third_party: sync third_party/gopkg.in/yaml.v1
docs: fix a typo
Merge pull request #224 from bcwaldon/typo

docs: fix a typo
Documentation: More specific link to fleet config.

Add an anchor tag to the url to take person directly to config section.
Merge pull request #217 from ecnahc515/patch-1

Fix broken link to fleet config
userdata: change handling of bad userdata

Don't fail after encountering bad userdata. Continue processing the metadata
and then exit. This will allow people with bad userdata to actually log in and
see the error.
flags: add oem flag

The oem flag will allow each of the OEMs to specify one flag only, acting as a
shortcut to their specific configuration. This will allow us to update which
options each OEM uses when running cloudinit.
flags: move the flags into their own namespace