remove unused hash method on string

app/javascript/src/javascripts/blacklists.js

@@ -62,7 +62,6 @@ Blacklist.update_sidebar = function() {
     var item = $("<li/>");
     var link = $("<a/>");
     var count = $("<span/>");
-    var hash = entry.tags.hash();
 
     link.text(entry.tags);
     link.click(Blacklist.toggle_entry);

app/javascript/src/javascripts/utility.js

@@ -150,15 +150,6 @@ Utility.is_global_hook_defined = function(path) {
   return typeof obj === 'function';
 }
 
-String.prototype.hash = function() {
-  var hash = 5381, i = this.length;
-
-  while(i)
-    hash = (hash * 33) ^ this.charCodeAt(--i)
-
-  return hash >>> 0;
-}
-
 $.fn.selectRange = function(start, end) {
   return this.each(function() {
     if (this.setSelectionRange) {