Add rounding.

Based on http://jinja.pocoo.org/docs/templates/#round.

Author: addyosmani

demo.html

@@ -54,6 +54,13 @@ <h3>limitFrom(1,2)</h3>
 
     <h3>wordcount</h3>
     {{'Hello World' | wordcount}}
+
+    <h3>round</h3>
+    {{ 45.35 | round }}
+
+    <h3>round(1, 'floor')</h3>
+    {{ 45.35 | round(1, 'floor') }}
+
 </template>
   <script>
 	var template = document.getElementById('view');

filter-round.js

@@ -0,0 +1,22 @@
+/**
+ * Round a number by a specific precision or method
+ * @param  {integer} val       
+ * @param  {integer} precision 
+ * @param  {string} method
+ * @return {string} 
+ */
+PolymerExpressions.prototype.round = function (val, precision, method) {
+    precision = precision || 0;
+    var factor = Math.pow(10, precision);
+    var rounder;
+
+    if (method == 'ceil') {
+        rounder = Math.ceil;
+    } else if (method == 'floor') {
+        rounder = Math.floor;
+    } else {
+        rounder = Math.round;
+    }
+
+    return rounder(val * factor) / factor;
+};

polymer-filters.html

@@ -8,6 +8,7 @@
 <script src="filter-replace.js"></script>
 <script src="filter-startsWith.js"></script>
 <script src="filter-wordcount.js"></script>
+<script src="filter-round.js"></script>
 
 <!--
 A collection of Polymer filters for formatting values of expressions for display to users
@@ -56,6 +57,12 @@
 
     {{'Hello World' | wordcount}}
 
+####Rounding
+
+    {{ 45.35 | round }}
+
+    {{ 45.35 | round(1, 'floor') }}
+
 @element polymer-filters
 @blurb A collection of Polymer filters for formatting values of expressions for display to users
 @homepage http://addyosmani.github.io/polymer-filters