LH: I have fixed issues in the PR and incorporated changes
from a sister PR by @djankovic (git author: Dom J). I also
made sure the UTF-8 files were readable without Chinese
fonts and added their downloading to the examples test suite.
... instead of hard-coding "make".
First, we check the value of `$MAKE`. If it's unset, we look for `gmake`
in the `$PATH`. If it's missing, we assume it's `make`.
This fixes the testsuite where GNU Make is installed as `gmake`.
The new example is called file_server and it's basically
the same as web_server was. The name is clearer than the
original, all examples being "Web servers".
The new example is also tested and the test suite has
been refactored a little.