Strip invalid options rather than throwing fatal

Fatal error throw when invalid options are passed to the definition
kills the run, which seems excessive, and worse will kill the daemon
entirely when chef-client is running in daemonized mode. Instead, log
an error and strip any invalid options, then continue the run.
Raising rather than continuing on error
Merge pull request #56 from brightcove/remove-fatal-error

Use `raise` rather than `Application.fatal` to prevent demonized chef-client, from exiting.