Gofig Integration / Namespace Change

[akutz]

This patch does away with the core/config package and instead uses the Gofig project for all of the configuration responsibilities. Additionally all of the REX-Ray properties are now under the rexray namespace in the YAML configuration. What was once "host" is now "rexray.host." These changes are reflected in the documentation.

This also handles issue #186.

[akutz]

Hi @clintonskitson,

Please test this PR's build against some real data and let me know whether it's safe to merge. Thanks!

[clintkitson]

@akutz

DEBU[0000] invoking service start                        os.Args=[./rexray start -l debug]
Starting REX-Ray...DEBU[0000] trying to start service                       client=/tmp/uwrVGTJxstSECXhggEqghJBXDpmSQXnd.sock
Start the service

Usage: 
  rexray service start [flags]

Flags:
      --client="": Socket the daemon uses to communicate to the client
      --force[=false]: Forces the service to start, ignoring errors
  -f, --foreground[=false]: Starts the service in the foreground

Global Flags:
  -c, --config="": The path to a custom REX-Ray configuration file
  -?, --help[=false]: Help for start
  -h, --rexrayHost="tcp://:7979": The REX-Ray host
  -l, --rexrayLogLevel="warn": The log level (error, warn, info, debug)
  -v, --verbose[=false]: Print verbose help information


Error: unknown flag: --logLevel