Remove Lucid/ppa instructions from SAIO guide

Lucid won't EOL until May of 2014; but I stopped trusting that ppa a long time
ago. Besides with the requires for dnspython and mock where they're at you
almost can't install swift from source on any stock distro and expect tests to
pass with system packages - so we're looking at pypi for depends regardless.

While I'm in there:

* more explanation of <your-user-name> and a helpful find/sed for configs
* group the "setup ~/.bashrc" stuff with the "setup ~/bin" stuff
* some updates/fixes from my experience installing on CentOS
* remove region warnings from remakerings

Change-Id: Ie2e6b06959ab699d853e07e5b7e8cda7036a44fe