[AFS3-std] Quota for max. number of files per volumes

[Felix Frank]

>> Bear in mind that not only are additional RPCs needed, but the volume dump
>> format must be extended as well. I expect such an extension to be on the
>> agenda for the upcoming protocol upgrade?
> 
> If it's not, well, we should be talking about it. This wouldn't be the
> only proposal that will require the ability to be backed up!

As always, I'm not sure whether I'm reading your hints correctly ;-p

Regardless, here goes for RxOSD (or should I repost in a separate thread?):
In the header:
	- tag 'P' (Int32) = OSD policy
In any vnodes:
	- tag 'u' (Int32) = last usage time (timestamp)
In directory vnodes:
	- tag 'P' (Int32) = Policy Index
In file vnodes:
	- tag 'z' (ByteStringWithLength)
			= string representation of OSD metadata
	- tag 'x' (Int32) = "OSD file is online" flag
	- tag 'y' (Int64 via DumpDouble() in OpenAFS)
			= file length, for OSD-files only

It strikes me as a little odd myself for me to propose yet another 
32-bit on-wire timestamp here - I guess we'll have to revamp the RxOSD 
protocol in order to match the upcoming AFS draft?

  - Felix