Add support for versioning via VERSION.sh - cleanup branding
This adds support for setting the package version and other information
by setting VERSION.sh. This allows us to change the version without having
to change configure.ac and running autogen.sh.
I also cleaned up the branding, using macros to replace the brand name and
other items in the files. This will allow us to rebrand the package by
simply editing or replacing VERSION.sh. When you run configure, the first
thing it will print is the branded package name and version.
I also cleaned up some obsolete files.