Missing Accept header

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Davdroid does not send the HTTP Accept header, which triggers a lot of rules when used with a service behind mod_security (or other web application firewalls).

Thus, davdroid should send the Accept header and advertise which Content-Types are accepted.

Thanks for the suggestion. Because DAVdroid only accepts XML for PROPFIND/REPORT requests and iCal/VCard files for GET, it should send appropriate Accept headers.

Great! Thanks for the fast fix.