[web] Better doc for installing the nailgun dev env

[Daniele Pizzolli]

The current doc can be improved to provide a seamless experience to
newcomers.

[Daniele Pizzolli (daniele-pizzolli)]

I do not know why hudson-openstack does not add by default the proposed fix:
https://review.openstack.org/#/c/201996

[Sebastian Kalinowski (prmtl)]

But please describe in the bug what is the exact problem. Description saying that it could be "improved" do not tell nothing what is wrong.

[Daniele Pizzolli (daniele-pizzolli)]

The current shell commands need user presence for useless confirmations
about package installation or default input.

There also some missing steps (dependencies, build commands).

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/201996
Committed: https://git.openstack.org/cgit/stackforge/fuel-web/commit/?id=f8008e2ee936664ca0866be2f32791fc889eff7b
Submitter: Jenkins
Branch: master

commit f8008e2ee936664ca0866be2f32791fc889eff7b
Author: Daniele Pizzolli <email address hidden>
Date: Fri Jul 10 15:09:10 2015 +0200

    Better doc for installing the nailgun dev env

    - every command can run unattended
    - following them produce a reliable installation (a poor man's literate
      programming)
    - works well with isend-mode.el
    - remove bashism (source for .)

    Closes-Bug: #1474747
    Change-Id: Iab0cc0e17dfa113c9194793f239f57f91492cf35