Add Copy Timestamp

A button that will copy the current timestamp has been added.

clock.js

@@ -46,3 +46,14 @@ function startTime(){
   }
   //document.getElementById('JStz').innerHTML = current_tz;
 }
+
+function copy_timestamp() {
+  var copyText = document.getElementById("time_body").innerText;
+  var temp_element = document.createElement("textarea");
+  document.body.appendChild(temp_element)
+  temp_element.value = copyText;
+  temp_element.select();
+  temp_element.setSelectionRange(0,999);
+  document.execCommand("copy");
+  document.body.removeChild(temp_element);
+}