bundles/dovecot: some fixes

- fix postfix/myhostname default
- ensure old_stats plugin is enabled
- ensure permissions for old_stats plugin
- ensure /etc/dovecot/ssl exists
- remove unneeded configuration files

bundles/dovecot/items.py

@@ -2,6 +2,10 @@
 # by this bundle
 repo.libs.tools.require_bundle(node, 'postfix')
 
+directories = {
+    '/etc/dovecot/ssl': {},
+}
+
 files = {
     '/etc/dovecot/dovecot.conf': {
         'content_type': 'mako',
@@ -25,6 +29,24 @@ files = {
             'svc_systemd:dovecot:restart',
         },
     },
+    '/etc/dovecot/conf.d/auth-system.conf.ext': {
+        'delete': True,
+        'needs': {
+            'pkg_apt:'
+        },
+        'triggers': {
+            'svc_systemd:dovecot:restart',
+        },
+    },
+    '/etc/dovecot/conf.d/10-auth.conf': {
+        'delete': True,
+        'needs': {
+            'pkg_apt:'
+        },
+        'triggers': {
+            'svc_systemd:dovecot:restart',
+        },
+    },
 }
 
 actions = {
@@ -33,6 +55,7 @@ actions = {
         'unless': 'test -f /etc/dovecot/ssl/dhparam.pem',
         'cascade_skip': False,
         'needs': {
+            'directory:/etc/dovecot/ssl',
             'pkg_apt:'
         },
         'triggers': {