Configure header filename in options instead of constructor

[hschletz]

The purpose of the filename passed to the ZipStream constructor is unclear at a first glance. A closer look reveals that it is used for the HTTP header, which is not sent by default.

As sending headers is configured in the Archive object, so should the filename.

Unfortunately, this would break BC because the argument is the first one.

[maennchen]

Tracked via #224