Add devbox and update to latest Gren version.

Author: robinheghan

Makefile

@@ -28,9 +28,9 @@ clean:
 $(browser_examples):
 	@echo "Compiling $@"
 	@cd "./$@/";\
-	gren make ./src/Main.gren --output=./Example.html
+	npx gren make ./src/Main.gren --output=./Example.html
 
 $(node_examples):
 	@echo "Compiling $@"
 	@cd "./$@/";\
-	gren make ./src/Main.gren --optimize --output=./app
+	npx gren make ./src/Main.gren --optimize --output=./app

cat/gren.json

@@ -4,7 +4,7 @@
     "source-directories": [
         "src"
     ],
-    "gren-version": "0.4.0",
+    "gren-version": "0.4.5",
     "dependencies": {
         "direct": {
             "gren-lang/core": "5.0.0",