Introduced Sympa::Tools::Text::slurp() to slurp text file applying Unicode sanitization and normalization. Note: Though Unicode::Normalize and Unicode::UTF8 are optional now, they would be mandatory in the future.

Test: t/pod-syntax.t: Test::Pod 1.40 mistakenly complains about the construct L<text|url>. Use 1.41 or later.

See https://rt.cpan.org/Public/Bug/Display.html?id=129066

Test-PerlTidy 20190305.001 requires later version of Perl::Tidy which may break the past formatting.  As a workaround, force sticked version of Test::PerlTidy.

  - HTTP/1.1 is supported thanks to LWP::UserAgent.
  - Now it has user, passwd, timeout, ssl_version, ssl_ciphers and ca_verify parameters.
  - host, port and path parameters were obsoleted.  Use url instead.
  - cert parameter was obsoleted.

- Code::TidyAll added as develop requirement in cpanfile
- Add tidyall target to Makefile.am (to run it with the good options
  without pain)
- Add dot/dot.tidyallrc
- Add t/ and xt/ to perltidy test

Updating source texts according to fixes on en_US catalog

- Add cpanfile, specifying dependencies for running the xt tests
  (authors tests, not installation tests)