New Files section reachable from Agenda's top bar: a WebDAV browser
against /remote.php/dav/files/<user>/ with folder navigation, file
download-and-open (via FileProvider + a viewer Intent), upload from
the system file picker, delete, create folder, and rename (WebDAV
MOVE). Extends DavXml's existing multistatus parser with
getcontentlength/getlastmodified rather than writing a second parser,
since the response/propstat/status merging logic it already has is
the fiddly part.
Verified live against the real account: browsed real folders/files,
created and deleted a test folder, and confirmed a file downloads
and reaches a view Intent correctly (no viewer app installed on the
emulator to actually open it, but the FileProvider hand-off worked).
RomanNum3ral
b8fdd9b421
