[PATCH 0/4] Repository format version check series.

This series is what I've been cooking for the past several days, partly based on patch from Martin Atukunda but with hopefully smaller impact.

[PATCH 1/4] Repository format version check. [PATCH 2/4] Check repository format version in enter_repo(). [PATCH 3/4] init-db: check template and repository format. [PATCH 4/4] setup_git_directory(): check repository format version.

The first in the series adds the core.repositoryformatversion configuration item. The current repository format version is defined as version 0, and is the same as not having that in the configuration file.

The second one adds a repository format version check to enter_repo(). This function is used to verify the path given by the user, either from the command line or over the network, is a valid git repository by daemon, upload-pack (which runs on the other end when you run fetch-pack or clone-pack), and receive-pack (which runs on the other end when you run send-pack).

The third one makes sure we do not reinitialize a repository whose format version we do not understand, do not copy template files from unmatching version into a new repository, and record the repository format version in a newly created repository.

The last bit in the series adds the same check code to setup_git_directory(). Along with the earlier change to git-sh-setup that uses git-var to verify the repository, this gives the shell scripts the same repository format version check.

I'll push this out to the "master" sometime over the weekend, and hopefully merge it into "maint" and cut the next 1.0rc on Wednesday. Let's hope that will be the last 1.0rc.