include git commit and/or env vars

[ORESoftware]

when logging out metafields

var Log = jlog.createLogger(env: []string{"git_commit"})

so then meta would become like:

[bunion, date, appname, hostname, pid, {env: {git_commit:"xyz"}}, []]

[ORESoftware]

it probably is going to have to be something like this:

[bunion, date, appname, hostname, pid, [], {git_commit:"xyz"}, {custom:"fields"}]

then maybe when we log things, it could look like:

date appname WARN ((env)FOO=bar)

nah that's no good