Fix z-push routine in upgrade script

install/upgrade/0.9.8-29.sh

@@ -86,6 +86,16 @@ fi
 # Install and configure z-push
 if [ ! -z "$MAIL_SYSTEM" ]; then
     echo "(*) Installing Z-Push..."
+    # Remove previous Z-Push configuration
+    rm -rf /etc/z-push/*
+    
+    # Disable apt package lock to install z-push
+    mv /var/lib/dpkg/lock-frontend /var/lib/dpkg/lock-frontend.bak
+    mv /var/lib/dpkg/lock /var/lib/dpkg/lock.bak
+    mv /var/cache/apt/archives/lock /var/cache/apt/archives/lock.bak
+    mv /var/lib/dpkg/updates/ /var/lib/dpkg/updates.bak/
+    mkdir -p /var/lib/dpkg/updates/
+
     apt="/etc/apt/sources.list.d"
     if [ "$os" = 'ubuntu' ]; then
         echo "deb http://repo.z-hub.io/z-push:/final/Ubuntu_$release/ /" > $apt/z-push.list
@@ -103,26 +113,29 @@ if [ ! -z "$MAIL_SYSTEM" ]; then
         APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE=1 apt-key add /tmp/z-push_signing.key > /dev/null 2>&1
     fi
 
-    apt-get -qq update > /dev/null 2>&1
-    apt-get -qq -y install z-push-common z-push-backend-imap z-push-backend-combined z-push-autodiscover > /dev/null 2>&1
+    apt-get -qq update
+    apt-get -qq -y install z-push-common z-push-backend-imap z-push-backend-combined z-push-autodiscover
 
-    # Copy configuration files
-    if [ -z /etc/z-push/ ]; then
-        echo "(I) Adding Z-Push configuration directory"
-        mkdir -p /etc/z-push/
-    fi
+    echo "(I) Adding Z-Push configuration directory"
+    mkdir -p /etc/z-push/
     cp -f $hestiacp/zpush/z-push.conf.php /etc/z-push/
     cp -f $hestiacp/zpush/imap.conf.php /etc/z-push/
 
     # Set permissions - chmod 777 needs further testing!
-    if [ -z /var/log/z-push ]; then
-        echo "(I) Adding Z-Push logs directory"
-        mkdir -p /var/log/z-push
-    fi
+    echo "(I) Adding Z-Push logs directory"
+    mkdir -p /var/log/z-push
+
     chmod 777 /var/lib/z-push
     chown -R www-data:www-data /var/lib/z-push
     chmod 777 /var/log/z-push
     chown -R www-data:www-data /var/log/z-push
+
+    # Enable apt package lock
+    mv /var/lib/dpkg/lock-frontend.bak /var/lib/dpkg/lock-frontend
+    mv /var/lib/dpkg/lock.bak /var/lib/dpkg/lock
+    mv /var/cache/apt/archives/lock.bak /var/cache/apt/archives/lock
+    rm -rf /var/lib/dpkg/updates/
+    mv /var/lib/dpkg/updates.bak/ /var/lib/dpkg/updates/
 fi
 
 # Update default page templates