Typos from Perl5 (2011- Episode 4) (#1053)

* Typos from Perl5 (2011- Episode 4)

* Update dictionary.txt

Re-adding the 3 suppressions of
https://github.com/codespell-project/codespell/pull/874/files

* Correction: were'nt->weren't

* Applying @luzpaz 's suggestions