webdav: Fix return code on DELETE of absent file

Due to compatibility concerns with MS Office 2010, Milton in some
cases turns a 404 reply into 401. Atlas noticed this and complained.

Milton only does this for anonymous requests, however when using client
certificates, from the point of view of Milton the session is anonymous
as no HTTP level authentication was performed.

This patch adds an X509AuthenticationHandler for Milton. It doesn't
actually do any authentication, but it is sufficient to let Milton
discover that the request has been authenticated and return the
correct error code.

Target: trunk
Require-notes: yes
Require-book: no
Request: 2.11
Request: 2.10
Request: 2.9
Request: 2.8
Request: 2.7
Request: 2.6
Acked-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Acked-by: Paul Millar <paul.millar@desy.de>
Patch: https://rb.dcache.org/r/7614/
ftp: ensure client command line is available in access log

Fix that access log for FTP doors so that all responses include
the corresponding client's command line.  Previously, additional
responses (for commands that result in multi-line responses)
and all responses to certain commands (STOR and RETR) were
logged without the client's command line.

Target: master
Patch: https://rb.dcache.org/r/7607/
Acked-by: Gerd Behrmann
Acked-by: Karsten Schwank
Request: 2.11
Request: 2.10
webdav: Fix reported content length for partial GETs

When a client requests a byte range beyond the end of the file,
Milton fails to take the file length into account. The consequence
is that we claim to provide a longer body than we do and that
the reported entity length in the Content-Range header is wrong.

This patch resolves the issue by fixing the range in our
custom response handler.

Resolves a compatibility issue with ARC.

Target: trunk
Require-notes: yes
Require-book: no
Request: 2.11
Request: 2.10
Request: 2.9
Request: 2.8
Request: 2.7
Request: 2.6
Acked-by: Paul Millar <paul.millar@desy.de>
Patch: https://rb.dcache.org/r/7615/
cells: Delete pcells related classes

Acked-by:
Target: master,  2.6, 2.10, 2.11
Require-book: no
Require-notes: yes

We removed the remaining pcells classes from the dcache code. There is a separate pcells repo on github now where all the pcells related code can be found. Pcells however has dependencies against the dCache code.

Patch: http://rb.dcache.org/r/7468/