Added mapper using remote procedure calls
Wrapped json.RawMessage in a struct

Avoids having to using json.RawMessage([]byte("null")).
Separated Codec from Reader
Separated Master and Slave code into package

Return when results are received, not when qsub finishes.
Combined addr and port into a single parameter
Exited server on Accept error

Made codecs state-less.
Added Print task to example.
Allowed tasks to have nil input/output

Removed Task() from Map interface
Used default location for stdout and stderr
Add eval function using interface{}s
Remove grideng
Move rpc to grideng
Remove files in root