[OSGeoLive] update proj overview and quickstart

[Astrid Emde (OSGeo)]

Hello,

I opened a ticket for proj.

We should update the documentation. In our documentation we still call 
the project proj4 and use an old logo.

I collected the tasks in a ticket 
https://trac.osgeo.org/osgeolive/ticket/2298

How should we proceed as the files are still called proj4_overview.rst 
or proj4_quickstart.rst and files in the folder proj4 - rename them? or 
keep the name?

Astrid