No longer depend on libltdl from the libtool package. The
winradio/linradio/wg313api backend still depends on libdl, but since it
is only compiled on POSIX, it will use the POSIX supplied libdl.
Update documentation to remove references to libltdl.
Static libs are generally not wanted so disable their builds by default.
Remove references to '--disable-static' from documentation and example
scripts.
Removed README_VB as its info is now embedded in the build-VB.NET.sh
script and is output into a custom README file upon creation of the ZIP
archive.
Added README.scripts to document reason for the directory and included
scripts.
