astrolib installation

Location: astrolib is currently installed under /opt/astro.
astrolib is an IDL add on. Download the astron.tar.gz file from the ftp site. Astrolib has no version number, so I take the date of the last listed change as the version number.

set package = "astrolib-<version>"
set location = "/opt/astro"
mkdir $location/IDL/$package
cd $location/IDL/$package
tar -zxf astron.tar.gz