Renaming savannadashboard directory to saharadashboard

* Renaming savannadashboard directory to saharadashboard which
also includes updating all of the places where that package
is referenced.
* Also including some renaming in the documentation.
* Changing the name of the top level panel to Sahara
* Changing the name of the top level Dashboard class to SaharaDashboard

Partial-Implements: blueprint savanna-renaming-dashboard

Change-Id: If51b85d22ec7798c214c56189359260198e69374
Changing "Savanna" to "Sahara" in basic strings

Changing "Savanna" to "Sahara" in basic strings as part of the
project renaming effort.  The strings changed here are mostly
of the most basic nature and mostly affect only displayed text.

Partial-Implements: blueprint savanna-renaming-dashboard

Change-Id: Ifdbff723894a2b6fb98e95e1f1595f6712ad662a