Release 6.22.0: Introduced some new configuration values to simplify the deployment of a branded OXUpdater and OLOX20

[changerequest]

New values in updater.properties:
com.openexchange.outlook.updater.downloadName
com.openexchange.outlook.updater.productName
com.openexchange.outlook.updater.icon

New file oxtender2.properties contains:
com.openexchange.outlook.updater.oxtender2.baseNam e
com.openexchange.outlook.updater.oxtender2.product Name
com.openexchange.outlook.updater.oxtender2.icon

- *.downloadName names the file name of the updater installer that can be downloaded from the web gui.
- *.productName defines the name of the updatable product that will be shown within the outlook updater
*.baseName defines a basic filename for the corrsponding binary files that are placed in /opt/open-xchange/files. It has to be statet without locale but with file ending.
- *.icon contains possibly bytecode for an icon that can be shown next to the product name within the outlook updater