Added some changes to call and added builtins

- call now supports calling invokables by string
- call now takes as arguments a listable of positional args, and a hashable of keyword args
- added strs:split, strs:join, and strs:has-prefix
- added new lists module with lists:first
- added time:sleep

cmd/cmsh/main.go

@@ -24,6 +24,7 @@ func main() {
 		ucl.WithModule(builtins.Itrs()),
 		ucl.WithModule(builtins.OS()),
 		ucl.WithModule(builtins.Strs()),
+		ucl.WithModule(builtins.Lists()),
 		ucl.WithModule(builtins.Time()),
 	)
 	ctx := context.Background()

cmd/playwasm/jsiter.go

@@ -27,6 +27,7 @@ func initJS(ctx context.Context) {
 		ucl.WithModule(builtins.Strs()),
 		ucl.WithModule(builtins.Time()),
 		ucl.WithModule(builtins.Itrs()),
+		ucl.WithModule(builtins.Lists()),
 		ucl.WithOut(ucl.LineHandler(func(line string) {
 			invokeUCLCallback("onOutLine", line)
 		})),