Docker example 2

[gabrielhesposito]

this is a re-branch of #204 w/ spelling corrections in the README, too many commits in the old branch.

Motivation: use in my personal website that is docker based.

use case for anyone using docker across their infrastructure, if service(s) run inside containers remote_syslog2 would need to run inside a container - in order to access the file system * properly to ensure those service(s) remain properly configured with respect to r/w/x.

*file system could be block storage like devicemapper or LVM or something like OverlayFS.

Copy paste from #204

tested user
1 rs2 0:00 remote_syslog -D
tested output
2017-07-19 23:52:07 INFO remote_syslog.go:55 Connecting to logs.papertrailapp.com:514 over tls
build instructions
docker build --build-arg VERSION=v0.19 -t rs2 .
run (in background, docker ps to confirm)
docker run --name rs2 -d rs2