Add stub on version and how to luanch trojita

source/2/2.1/2.1.5/trojita.rst

@@ -0,0 +1,12 @@
+Chapter 2.1.5 Trojita
+=====================
+
+Trojita is the default IMAP email client of Lubuntu.
+
+Version
+-------
+Lubuntu Ships with version 0.7-0 of trojita.
+
+How to launch
+--------------
+To launch trojita from the menu -> Internet -> trojita with the icon that looks like an envolope or run trojita from the command line. 

source/2/2.1/Internet_Applications.rst

@@ -8,3 +8,4 @@ Chapter 2.1 Internet Applications
    2.1.1/firefox
    2.1.2/qtransmission
    2.1.3/Quasel_IRC
+   2.1.5/trojita