Make shell login in fuel-menu really interactive

Enables job control in a shell by making use of
the "screen" utility
Closes-Bug: #1469137
Change-Id: I3f14dc214286e5a7dfcd9dff9dd004bef8414b2f

fuelmenu/fuelmenu/modules/shell.py

@@ -44,7 +44,10 @@ class shell():
         self.parent.mainloop.screen.stop()
         message = "Type exit to return to the main UI."
 
-        subprocess.call("clear ; echo '%s';echo;bash -i" % message, shell=True)
+        subprocess.call(
+            "screen bash -c 'clear; echo %s ; echo; bash -i'" % message,
+            shell=True
+        )
         self.parent.mainloop.screen.start()
 
     def refresh(self):

specs/nailgun.spec

@@ -226,6 +226,7 @@ Requires: python-netifaces
 Requires: python-urwid >= 1.1.0
 Requires: PyYAML
 Requires: python-ordereddict
+Requires: screen
 
 %description -n fuelmenu
 Summary: Console utility for pre-configuration of Fuel server