update Z-Push to 2.4.4

Starting with 2.4, Z-Push no longer provides tarballs on their download server. The only options are getting the code from their git repository or using one of their distribution packages. Their Ubuntu 18.04 packaes don't seem to actually work in Ubuntu 18.04, so thinking ahead that's currently a bad choice. In 78d1c9be6e we switched from doing a git clone to using wget on their downloads server because of a problem with something related to stash.z-hub.io's SSL certificate. But wget also seems to work on their source code repository, so we can use that.

CHANGELOG.md

@@ -6,6 +6,7 @@ In Development
 
 * Update to Nextcloud 13.0.5.
 * Update to Roundcube 1.3.7.
+* Update to Z-Push 2.4.4.
 
 v0.28 (July 30, 2018)
 ---------------------

setup/zpush.sh

@@ -22,8 +22,8 @@ apt_install \
 phpenmod -v php7.0 imap
 
 # Copy Z-Push into place.
-VERSION=2.3.9
-TARGETHASH=60087b97e4b1c73db096e252cf893c75df556907
+VERSION=2.4.4
+TARGETHASH=104d44426852429dac8ec2783a4e9ad7752d4682
 needs_update=0 #NODOC
 if [ ! -f /usr/local/lib/z-push/version ]; then
 	needs_update=1 #NODOC
@@ -32,12 +32,14 @@ elif [[ $VERSION != `cat /usr/local/lib/z-push/version` ]]; then
 	needs_update=1 #NODOC
 fi
 if [ $needs_update == 1 ]; then
-	wget_verify http://download.z-push.org/final/2.3/z-push-$VERSION.tar.gz $TARGETHASH /tmp/z-push.tar.gz
+	# Download
+	wget_verify "https://stash.z-hub.io/rest/api/latest/projects/ZP/repos/z-push/archive?at=refs%2Ftags%2F$VERSION&format=zip" $TARGETHASH /tmp/z-push.zip
 
-	rm -rf /usr/local/lib/z-push
-	tar -xzf /tmp/z-push.tar.gz -C /usr/local/lib/
-	rm /tmp/z-push.tar.gz
-	mv /usr/local/lib/z-push-$VERSION /usr/local/lib/z-push
+	# Extract into place.
+	rm -rf /usr/local/lib/z-push /tmp/z-push
+	unzip -q /tmp/z-push.zip -d /tmp/z-push
+	mv /tmp/z-push/src /usr/local/lib/z-push
+	rm -rf /tmp/z-push.zip /tmp/z-push
 
 	rm -f /usr/sbin/z-push-{admin,top}
 	ln -s /usr/local/lib/z-push/z-push-admin.php /usr/sbin/z-push-admin