dashboard3: add minify option in Makefile

also:
- add .gitignore for dashboard3.min.* files so they don't get committed

Author: exurd

dashboard/.gitignore

@@ -0,0 +1 @@
+dashboard3.min.*

dashboard/assets/dashboard3/Makefile

@@ -1,4 +1,10 @@
-all: dashboard
+all: dashboard minify
 
 dashboard: Dashboard.hx
 	haxe -main Dashboard -D analyzer-optimize -dce full -D js-es=6 -js dashboard3.js
+
+minify: dashboard3.js dashboard3.css ../../dashboard3.html
+# npm i -g terser csso-cli html-minifier-next
+	terser dashboard3.js -c -m --ecma 2015 -o dashboard3.min.js
+	csso dashboard3.css -o dashboard3.min.css
+	html-minifier-next --collapse-whitespace --minify-js true ../../dashboard3.html -o ../../dashboard3.min.html