* Added etcd installation instructions ptr
(cannot run integ tests w/o it).
* Removed unnecessary mercurial instructions
(install works w/o mercurial).
* Moved pre-commit hook installation instructions from development
loop to git clone section (it's a one time setup).
* Ditto for "setting upstream remote to no_push".
* Gathered Go install/upgrade discussion to one section.
* Put build/test instructions between checkout and commit.
Formerly, build was up before fork (odd), and test was
tacked at end of doc.
* Brought text into sync with the Workflow fig:
* Assured 1:1 correspondence between numbered figure steps
and numbered section headers - had no numbers before.
* Used "$working_dir", "$user" and "myfeature" in text to
match figure.
Timo Reimann
xiangpengzhao
Mike Spreitzer
Alexander Campbell
Michael Taufen
Guang Ya Liu
Luis Valdes
Will Sean Don
jay vyas
Jeffrey Regan
Łukasz Oleś
Jeff Grafton
Michelle Noorali