Merge branch '1.5' into 1.5-alpine_3.8

core/admin/Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3-alpine
+FROM python:3-alpine3.7
 
 RUN mkdir -p /app
 WORKDIR /app

core/dovecot/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:edge
+FROM alpine:3.7
 
 RUN echo "@testing http://nl.alpinelinux.org/alpine/edge/testing" >> /etc/apk/repositories \
  && apk add --no-cache \

core/dovecot/sieve/report-ham.sieve

@@ -1,3 +1,11 @@
-require "vnd.dovecot.execute";
+require ["vnd.dovecot.execute", "copy", "imapsieve", "environment", "variables"];
+
+if environment :matches "imap.mailbox" "*" {
+  set "mailbox" "${1}";
+}
+
+if string "${mailbox}" "Trash" {
+  stop;
+}
 
 execute :pipe "mailtrain" "ham";

core/none/Dockerfile

@@ -1,5 +1,5 @@
 # This is an idle image to dynamically replace any component if disabled.
 
-FROM alpine
+FROM alpine:3.7
 
 CMD sleep 1000000d

core/postfix/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine
+FROM alpine:3.7
 
 RUN apk add --no-cache postfix postfix-sqlite postfix-pcre rsyslog python py-jinja2