[enh] Allow for dovecot configuration extensions

data/hooks/conf_regen/25-dovecot

@@ -26,11 +26,18 @@ do_pre_regen() {
       's/^\(listen =\).*/\1 */' \
       "${dovecot_dir}/dovecot.conf"
   fi
+
+  mkdir -p "${dovecot_dir}/yunohost.d"
+  cp pre-ext.conf "${dovecot_dir}/yunohost.d"
+  cp post-ext.conf "${dovecot_dir}/yunohost.d"
 }
 
 do_post_regen() {
   regen_conf_files=$1
 
+  sudo mkdir -p "/etc/dovecot/yunohost.d/pre-ext.d"
+  sudo mkdir -p "/etc/dovecot/yunohost.d/post-ext.d"
+
   # create vmail user
   id vmail > /dev/null 2>&1 \
     || sudo adduser --system --ingroup mail --uid 500 vmail

data/templates/dovecot/dovecot.conf

@@ -1,3 +1,5 @@
+!include yunohost.d/pre-ext.conf
+
 listen = *, ::
 auth_mechanisms = plain login
 
@@ -10,6 +12,7 @@ protocols = imap sieve
 
 mail_plugins = $mail_plugins quota
 
+
 ssl = yes
 ssl_cert = </etc/yunohost/certs/{{ main_domain }}/crt.pem
 ssl_key = </etc/yunohost/certs/{{ main_domain }}/key.pem
@@ -30,6 +33,7 @@ protocol imap {
   mail_plugins = $mail_plugins imap_quota antispam
 }
 
+
 protocol lda {
   auth_socket_path = /var/run/dovecot/auth-master
   mail_plugins = quota sieve
@@ -89,3 +93,4 @@ plugin {
   quota_warning3 = -storage=100%% quota-warning below %u # user is no longer over quota
 }
 
+!include yunohost.d/post-ext.conf

data/templates/dovecot/post-ext.conf

@@ -0,0 +1 @@
+!include_try post-ext.d/*.conf

data/templates/dovecot/pre-ext.conf

@@ -0,0 +1 @@
+!include_try pre-ext.d/*.conf