Use default genproclimit of -1 on setgenerate RPC.

The correct default for the genproclimit on the setgenerate RPC is -1.

ok @jcvernaleo.

jsoncmd.go

@@ -5728,8 +5728,7 @@ var _ Cmd = &SetGenerateCmd{}
 // NewSetGenerateCmd creates a new SetGenerateCmd. Optionally a
 // pointer to a TemplateRequest may be provided.
 func NewSetGenerateCmd(id interface{}, generate bool, optArgs ...int) (*SetGenerateCmd, error) {
-
-	genproclimit := 0
+	genproclimit := -1
 	if len(optArgs) > 1 {
 		return nil, ErrTooManyOptArgs
 	}
@@ -5758,7 +5757,7 @@ func (cmd *SetGenerateCmd) Method() string {
 func (cmd *SetGenerateCmd) MarshalJSON() ([]byte, error) {
 	params := make([]interface{}, 1, 2)
 	params[0] = cmd.Generate
-	if cmd.GenProcLimit != 0 {
+	if cmd.GenProcLimit != -1 {
 		params = append(params, cmd.GenProcLimit)
 	}
 

jsoncmd_test.go

@@ -1361,6 +1361,7 @@ var jsoncmdtests = []struct {
 		result: &SetGenerateCmd{
 			id:           testId,
 			Generate:     true,
+			GenProcLimit: -1,
 		},
 	},
 	{