Enhancement - Supports '--' on the command line

- Using '--' on the command line separates the left hand side, where
  task is free to interpret arguments in the usual way, and the right
  hand side, which is then assumed to be part of the task description,
  and is not interpreted by task.

html/task.html

@@ -138,6 +138,8 @@
                   <li>Fixed documentation errors (thanks to Thomas@BIC).
                   <li>The 'weekstart' configuration variable now controls the 'calendar'
                       command (thanks to Federico Hernandez).
+                  <li>Supports '--' argument to indicate that all subsequence arguments are
+                      part of the description, despite what they otherwise might mean.
                 </ul>
 
                 <p>