acu134934 fix rs_config example
acu134934 add short cases of usage for --version and --help commands to help banner
acu134934 print error message instead of stack trace on exceptions
acu134934 rs_config --get prints default value if value is not set
acu134934 make motd_update feature enabling/disabling work
Merge pull request #294 from rightscale/ivory_13_20_acu134934_rs_config_utility

rs_config iterate on QA