Added temperature conversation plugin

Plugins.md

@@ -79,4 +79,51 @@ Better readability on big resolutions screens (css)
 ol li .message {
   font-size: 1.5em;
 }
+```
+
+## Add converted temperature
+
+``` javascript
+// A Tentia plugin to automatically convert fahrenheit to celcius
+// and vice versa. Change the unit in the line: var unit = "F";
+
+$(document).ready(function() {
+  if(tentia_instance && tentia_instance.body) {
+    tentia_instance.body.addEventListener(
+      'DOMNodeInserted',
+      tmpConv,
+      false
+    );    
+  }
+});
+
+function tmpConv(e) {
+
+  var unit = "F"; // either F or C, the one you want to convert
+
+  var element = e.target;
+  if(element.parentNode != tentia_instance.body) return;
+
+  var message = $(element).find(".message");
+
+  var callback = f2cCallback;
+  if (unit == "C") callback = c2fCallback;
+
+  var regex = new RegExp("(-?[0-9]+) ?°? ?" + unit + "+", "ig");
+
+  text = message.html().replace(regex, callback);
+  message.html(text);
+}
+
+function f2cCallback(f, fahrenheit) {
+  fahrenheit = parseInt(fahrenheit, 10);
+  var celsius = (fahrenheit - 32) * 5 / 9;
+  return f + " (" + parseInt(celsius) + "°C)";
+}
+
+function c2fCallback(c, celsius) {
+  celsius = parseInt(celsius, 10);
+  var fahrenheit = celsius * 1.8 + 32;
+  return c + " (" + parseInt(fahrenheit) + "°F)";
+}
 ```