Add support for handling lrp messages

Signed-off-by: Momchil Atanasov <m.momchil@gmail.com>
Correctly handle SIGINT and SIGTERM

* reprunner no longer nils out the session on stop
* taskRep and lrpRep now spawn goroutines in their Run() methods.

Signed-off-by: Momchil Atanasov <m.momchil@gmail.com>
godeps

Signed-off-by: Momchil Atanasov <m.momchil@gmail.com>