Use XDGMENUMAKERTERM var to override terminal app

Check if an XDGMENUMAKERTERM environment variable is set. If it is, set
the default terminal emulator to it. This overrides any other setting.

src/xdgmenumaker

@@ -119,20 +119,24 @@ other = de.getName().encode('utf-8')
 other_icon = de.getIcon()
 # Find out which terminal emulator to use for apps that need to be
 # launched in a terminal.
-# First see if there is a user specified terminal emulator in the
+# First check if the XDGMENUMAKERTERM environment variable is set and use it if
+# it is.
+# Then see if there is a user specified terminal emulator in the
 # xdgmenumaker.cfg file.
-try:
-    config = ConfigParser.SafeConfigParser()
-    config.read(os.path.expanduser('~/.config/xdgmenumaker.cfg'))
-    terminal_app = config.get('Terminal', 'terminal')
-# if there isn't, on debian and debian-likes, use the alternatives
-# system, otherwise default to xterm
-except (ConfigParser.NoSectionError, ConfigParser.NoOptionError) as e:
-    if (os.path.exists('/etc/alternatives/x-terminal-emulator')
-            and os.path.exists('/usr/bin/x-terminal-emulator')):
-        terminal_app = '/usr/bin/x-terminal-emulator'
-    else:
-        terminal_app = 'xterm'
+terminal_app = os.getenv("XDGMENUMAKERTERM")
+if not terminal_app:
+    try:
+        config = ConfigParser.SafeConfigParser()
+        config.read(os.path.expanduser('~/.config/xdgmenumaker.cfg'))
+        terminal_app = config.get('Terminal', 'terminal')
+    # if there isn't, on debian and debian-likes, use the alternatives
+    # system, otherwise default to xterm
+    except (ConfigParser.NoSectionError, ConfigParser.NoOptionError) as e:
+        if (os.path.exists('/etc/alternatives/x-terminal-emulator')
+                and os.path.exists('/usr/bin/x-terminal-emulator')):
+            terminal_app = '/usr/bin/x-terminal-emulator'
+        else:
+            terminal_app = 'xterm'
 
 
 def main(argv):