AVRO-2481: Introduce Perl::Critic for linting the Perl bindings

[sekikn]

Make sure you have checked all steps below.

Jira

• My PR addresses the following Avro Jira issues and references them in the PR title. For example, "AVRO-1234: My Avro PR"
  • https://issues.apache.org/jira/browse/AVRO-2481
  • In case you are adding a dependency, check if the license complies with the ASF 3rd Party License Policy.

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

This PR adds linting feature to the Perl bindings. It also contains fixes for the existing violations.
I ran ./build.sh lint in the lang/perl directory and confirmed all violations were fixed.

Commits

• My commits all reference Jira issues in their subject lines. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation

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  • All the public functions and the classes in the PR contain Javadoc that explain what it does

[Fokko]

@sekikn The failed for an unknown reason. Can you rebase against lastest master?

[sekikn]

Sure! Rebased on master.