Initialize wo db only if nginx installed

install

@@ -279,15 +279,13 @@ wo_sync_db() {
         mkdir -p /var/lib/wo
 
         if [ -f /var/lib/ee/ee.db ]; then
-            # Copy the EasyEngine database
+            # Make a backup of the EasyEngine database
             cp /var/lib/ee/ee.db /var/lib/wo/dbase-ee.db
 
-            ###
-            # Clean WO installation
-            ###
-
+            # Copy ee database
             cp /var/lib/ee/ee.db /var/lib/wo/dbase.db
         else
+            if [ -d /etc/nginx/sites-available ]; then
 
                 # Create an empty database for WordOps
                 echo "CREATE TABLE sites (
@@ -371,7 +369,7 @@ wo_sync_db() {
             VALUES (\"$site\", \"$wo_site_current\", \"$wo_site_current_cache\", \"$wo_webroot\", \"$wo_site_status\", 0, 'ext4', 'mysql');" | sqlite3 /var/lib/wo/dbase.db
 
                 done
-
+            fi
         fi
 
         #        echo "UPDATE sites SET php_version = REPLACE(php_version, '5.6', '7.2');" | sqlite3 /var/lib/wo/dbase.db