Improve test file for Circulation (#175)

- Bug fix: add a missing #include.
- Add compile test for various functions and named parameters.
- Use a smaller digraph with lower bounds.
- Test eight instances instead of two.
- Remove the doc that was for the demo file.

prefix=@prefix@

exec_prefix=@exec_prefix@

libdir=@libdir@

includedir=@includedir@

Name: @PACKAGE_NAME@

Description: Library of Efficient Models and Optimization in Networks

Version: @PACKAGE_VERSION@

Libs: -L${libdir} -lemon

Cflags: -I${includedir}