If running on a Debian-based OS (this includes Ubuntu), it is highly recommended
to install this program as a package. In Debian and Ubuntu, feedgnuplot is in
the official repos, so all you need to do is

   sudo apt-get install feedgnuplot

Without a package, an installation can be done with

         perl Makefile.PL prefix=/usr/local
         make
         make install

This installs feedgnuplot to /usr/local. Adjust the paths as required.

Also, note that this is a self-contained utility. Usually running from the tree
works just fine:

         git clone https://github.com/dkogan/feedgnuplot.git
         cd feedgnuplot/bin
         ./feedgnuplot ...