Build AppImage with Ubuntu 18.04.

diff --git a/cdist b/cdist
index 8f8cb0e6b53e77a1410ee5d20e7507b1e24d425a..9e6be5f10d47b6e9b7779bb7e2621a843fae3fe9 100755 (executable)
--- a/cdist
+++ b/cdist
@@ -707,7 +707,7 @@ class LinuxTarget(DockerTarget):
 
 class AppImageTarget(LinuxTarget):
     def __init__(self, work):
-        super(AppImageTarget, self).__init__('ubuntu', '16.04', 64, work)
+        super(AppImageTarget, self).__init__('ubuntu', '18.04', 64, work)
         self.detail = 'appimage'
         self.privileged = True