Add readme field to metadata.json

Author: RKBoss6

apps/messageicons/metadata.json

@@ -7,6 +7,7 @@
   "type": "module",
   "tags": "tool,system",
   "supports": ["BANGLEJS","BANGLEJS2"],
+  "readme":"README.md",
   "provides_modules" : ["messageicons"],
   "default": true,
   "storage": [