libslider: split and move to modules and test app

apps/slidertest/metadata.json

@@ -6,12 +6,10 @@
   "icon": "app.png",
   "tags": "ui",
   "supports": ["BANGLEJS2"],  
-  "provides_modules": ["SliderInput"],
   "readme": "README.md",
   "storage": [
-    {"name":"libslider.img","url":"app-icon.js","evaluate":true},
+    {"name":"slidertest.img","url":"app-icon.js","evaluate":"true"},
-    {"name":"libslider.app.js","url":"app.js"},
+    {"name":"slidertest.app.js","url":"app.js"}
-    {"name":"SliderInput","url":"lib.js"}
   ]
 }