This kind of file includes translated entries, which causes spelling
check false positives, and makes the author tests and CI systems
checking those fail.

Files that have been autogenerated are of no interest because in many
cases we have little direct control over them.

The new python version makes codespell itself emit runtime warnings,
which confuses the test suite. Ignore thse for now.

These contain files that are not currently skept, and might contain
spelling errors from external sources.

Warned-by: codespell

Make sure all SYNOPSIS sections have compilable code.

Verify that the perl version we want to restrict ourselves in the coding
style is enforced through the test suite.

With «use warnings» some inermodule issues such as redefinitions of
symbols are not catched, because that is too late.

Define PERL in the unit test environment so that we can invoke the
detected interpreter.

And disable the now redundant syntax_ok() check from the strict.t unit
test.

This stops the madness of having to invent sequence numbers to be able
to order the test suite run. Instead we now honour the order of the
arguments passed to the runner.

This should reduce the check time significantly, as it stops checking
the program files by duplicate (for <script> and <script>.pl), and does
not scan the .git directory any longer.

Using double-quotes imposes a small performance penalty as the perl
parser needs to check if any interpolation is needed. Use double-quotes
only when the string contains single-quotes. Ideally we'd use
double-quotes too for escaped meta-characters that might otherwise be
confusing to immediately see if they need interpolation or not, but the
policy does not (currently) allow to ignore these.

Fixes ValuesAndExpressions::ProhibitInterpolationOfLiterals.

Warned-by: perlcritic

This marks all these files as script files, so that tools like
perlcritic do not misrecognize them as modules.

This test is useful for all perl code in the project, not just for the
scripts directory. Move it to the top level directory so that we don't
have to do strange things referencing sibling directories and similar.

These just clutter the code base, as adding modelines for each possible
editor out there does not scale, and they are currently not exhaustive
anyway.

Standard Test::Pod testing.