Add EquivalentArrayNoDatatypes filter

[kpaulisse]

Overview

This pull request adds a new filter called EquivalentArrayNoDatatypes which suppresses diffs like this one:

  Exec[my-command-here] =>
   parameters =>
     returns =>
      - ["0", "1"]
      + [0, 1]

Specifically, this implementation treats the string, integer, and float values of a given number as the same ("1" == 1 == 1.0) and treats the string representation of a symbol as the same as the string (":foo" == :foo).

Unit tests are updated to cover this filter and an integration test has been added. Filter documentation has also been updated.

Checklist

• Make sure that all of the tests pass, and fix any that don't. Just run rake in your checkout directory, or review the CI job triggered whenever you push to a pull request.
• Make sure that there is 100% test coverage by running rake coverage:spec or ignoring untestable sections of code with # :nocov comments. If you need help getting to 100% coverage please ask; however, don't just submit code with no tests.
• If you have added a new command line option, we would greatly appreciate a corresponding integration test that exercises it from start to finish. This is optional but recommended.

[ahayworth]

Seems okay to me! Thank you! 😄