added RPC start/stop support

rpc/api/args.go

@@ -2,6 +2,7 @@ package api
 
 import (
 	"encoding/json"
+
 	"github.com/ethereum/go-ethereum/rpc/shared"
 )
 
@@ -54,4 +55,4 @@ func (args *FilterStringArgs) UnmarshalJSON(b []byte) (err error) {
 	}
 	args.Word = argstr
 	return nil
-}
+}