slightly better docs for git instead of svn

Slightly better docs for git instead of svn

Not sure if this is 100% accurate, but better than all the SVN refs
that are there now.

R=iannucci@chromium.org, dpranke@chromium.org

Committed: https://chromium.googlesource.com/external/gyp/+/0bb67471bca068996e15b56738fa4824dfa19de0

[iannucci, 2015-04-29 00:48:06]

iannucci@chromium.org changed reviewers:
+ iannucci@chromium.org

[iannucci, 2015-04-29 00:48:06]

fwiw, lgtm

[scottmg, 2015-04-29 00:49:54]

On 2015/04/29 00:48:06, iannucci wrote:
> fwiw, lgtm

good enough for me!

[scottmg, 2015-04-29 00:50:02]

Committed patchset #2 (id:20001) manually as
0bb67471bca068996e15b56738fa4824dfa19de0 (presubmit successful).

[Dirk Pranke, 2015-04-29 01:06:31]

lgtm. I have a patch to add a 'fetch' recipe for gyp somewhere, but this is fine
in the meantime.

Thanks for working on this; it was on my to-do list but I hadn't gotten to it
yet.