Add some tools to simplify the use of git

[rstone]

Summary

Add some scripts that wraps some FreeBSD Project infrastructure
and simplifies using them with git. The scripts are:

• arcgit, which creates a series of reviews in Differential
• importgit, which applies a series of git commits to svn

[markj]

arcgit is a pretty handy script, thanks! It's slightly annoying that one has to remember to use "-r C1~..C2" instead of "-r C1..C2" for an inclusive range of commits, although I guess that's consistent with git commands. Maybe include the "~" in the usage message?

It'd also be useful to have some sort of semi-dry run mode. I just used it for the first time and wanted to try creating reviews without specifying any reviewers, but the interface doesn't allow that. I just commented out the section that adds them and manually added them in the browser after the reviews were created.

tools/tools/git/arcgit

43 ↗

(On Diff #4235)

This should be "-r commit1..".

[rstone]

Add -n option to arcgit to perform a dry run, and fix some typos.