add vfs unlink and rmdir tests webdav

implement webdav delete for collections webdav

add webdav op function for iterating directories webdav

add mkcol and delete interface to webdav backend, move webdav vfs logic to operation webdav

(0) -100 -30 -10 -4 +4 +10 +30 +100 +300 tip

mercurial