[PoC PATCH JGIT 0/2] Proof of concept code for Git Freenet transport

Hi JGit / Freenet community,

Here is some proof-of-concept code for Git-over-Freenet. I am sending this to see the feedback from communities.

The code need some more cleanups, so it it is not ready for apply (yet).

This is a real-life example

Push:
   $ git remote add fcp fcp://SSK@[my public key]^[my private key]/test.git
   $ ./jgit push fcp refs/remotes/origin/stable:refs/heads/master
 
 /ALTERNATIVLY/

   Insert a bare repository under USK@<.....>/test.git/-1/

Pull:
 $ ./jgit clone fcp://SSK@[my public key]^[my private key]/test.git

To workaround the metadata update problem, this client translate the path seperator to "-", that means:

On push:
   objects/aa/bbbbbbbb   --> USK@..../test.git-objects-aa-bbbbbbb/-1/
   refs/heads/xxx        --> USK@..../test.git-objects-ref-heads-xxx/-1/

On pull:
   To support uploading from jSite, 
    when we load the info/refs we first check USK@..../test.git-info-refs/-1/
    if it is unavailiable, we would use USK@..../test.git/-1/info/refs

   The "traditional" type (USK@..../test.git/-1/objects) repository is
   always added as an alternative objects database. No other info/alternatives 
   are supported

FIXME:
 - How to store the private key of repository?
   Currently, we use URI of form fcp://SSK@<public key>^<private key>/some-id
   This is quite ugly. Could we use a per remote Config ? How can I get remote
   name from transport?

 - Make pushing async, could we?