WebDAV feature not documented

[akuckartz]

linkeddata/warp#8 (comment) mentions that this software provides support for WebDAV. But that significant fact does not seem to be documented anywhere !

[chrysn]

WebDAV seems to be almost, but not quite supported; what works seems to be primarily where LDP uses the same methods as WebDAV. For practical support (which to me means that it works with GVFS and cadaver), at least the DAV: 1 header and the PROPFIND method are missing.

Both can be added easily as shown in the dav-usable-for-gvfs branch. (Feel free to build on it; I don't phrase this as a pull request because my testing was minimal (list directory, copy, rename and edit file), I did no tests on permissions, and those are my first lines of Go copy-pasting.)