Python 3 directly decodes the text when it is read(). If there is any
invalid UTF-8 character in the text an exception is thrown (IIRC it is
UnicodeDecodeError). Opening the file with `error='ignore'` avoids
throwing an exception and just ignores the invalid character. Since
this is only possible since Python version 3 there must be extra code
for older versions.
The test script has been enhanced. It now also uses a package which
contains a file with at least one invalid UTF-8 character.
Indirectly the scripts (at first the server test script) also document what needs to be done to setup a (local) server.
The productive client script can be used by everyone who wants to support daca@home, not only for testing. But i still think it is good to have it under /test to not lose too much clarity / lucidity in the /tools directory.