Added JS DOM element selector snippets

So not everyone uses jQuery. Who knew?

I've added snippets for the main vanilla JS DOM element selector
snippets.

snippets/javascript/javascript.snippets

@@ -205,3 +205,11 @@ snippet prop
 			configurable : ${0:boolean}
 		}
 	);
+snippet by.
+	${document}.getElementsByClassName('${class name})
+snippet by#
+	${document}.getElementById('${element ID})
+snippet qs
+	${document}.querySelector('${selectors})
+snippet qsa
+	${document}.querySelectorAll('${selectors})