Add an initial landing page for Git contributors summit

I'm working on a logo for our little event page, based on what Carmen
already made: the git logo with brightly coloured "branches" shooting
out of it / making a gorgeous pattern around it.

We were talking about an event page to have a single place to find and
archive resources (pre-reading, event recap, Code of Conduct), and to
hint to the larger event. Happy to create a GitHub Pages, if we have
an org / repo on GitHub. Alternatively ofcourse, we could just use a
repo's readme for all of this, while also storing all the assets
there.

Copy-wise, I was thinking of the following:

[jn: tweaked some text based on Floor's initial text]

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Change-Id: I2aa0f98a84e582407cd0f543ad58085efebb3a44
1 file changed
tree: 2af5bf918ed84773d590ee7c9814961385e20d7b
  1. index.md