First working version of the ispconfig roundcube

- Completly rebuild the container startup to be less brute-forcish
- All relevant configs now lie in the external volume
- DB init is only done if a new config is written.
- ENV Vars are only needed if you want to automatically write a config
- Cleaned up everything

src/db.inc.php

@@ -1,13 +1,15 @@
 <?php
+# DB Config style taken from the Debian maintainers, making things simpler
+# as PHP is easier to manage here than bash substituion magic.
+
 include_once("/var/roundcube/config/db.inc.php");
 
 switch ($dbtype) {
  case "sqlite":
-   $config['db_dsnw'] = "sqlite:///$basepath/$dbname?mode=0640";
+   $config['db_dsnw'] = "sqlite:///var/roundcube/config/sqlite.db?mode=0640";
    break;
  default:
    if ($dbport != '') $dbport=":$dbport";
-   if ($dbserver == '') $dbserver="localhost";
    $config['db_dsnw'] = "$dbtype://$dbuser:$dbpass@$dbserver$dbport/$dbname";
    break;
  }