update Why is this one better than other

README.md

@@ -13,6 +13,7 @@ This is a URL shorter written in Python with Flask als Webhandler. The Webserver
 * small and modern UI
 * posibility to use multiple domains
 * open source --> posibility to expand
+* very small and leightweight (at the moment the sourcecode is about 4mb)
 
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