[PATCH 0/3] git-svn-externals PoC (in a sh script)

Hello,

I have started a while back working on support for svn:externals support for git-svn, but since I'm not that satisfied with the current status of the patch, I haven't modified git-svn itself and just left the sh script I made as a PoC as it was.

There's still work to be done to it, but I the current version is functional enough to be probably found useful by more people than myself.

Current status follows:

    Current functionality:
     - fetches all the externals of an already svn-fetched repo
     - support for svn:externals refresh
     - if the location of the external has changed, the current working
       copy will be placed aside and a new directory will be created
       instead
     - if the remote URI is the same (maybe a verison bump, there will
       be a 'git svn rebase'
     - remove support (useful for testing purposes or clean restarts)
     - avoid zombie externals at all costs - in some repos empty
       svn:externals might exist; svn ignores such externals, so git should
       do the same

    TODO:
     - take into account the revision of an external, if it exists
     - do not do deep svn cloning, to avoid legthy operations, just pull HEAD
       (this actually needs changes in git-svn itself)
     - use/create shallow copies to git svn repos (one revision should be enough
       for most externals)
     - use submodules for externals

Any comments are welcome.