feat: Add `collect` and `collectFirst` functions

[adamhamlin]

Description

Adds two new functions: collect and collectFirst. See more info/discussion in #269.

• collect - Map+filter operation where undefined transformations are filtered out
• collectFirst - Map+find operation where the first defined transformation is returned

Checklist

• [X] Changes are covered by tests if behavior has been changed or added
• [X] Tests have 100% coverage
• [X] If code changes were made, the version in package.json has been bumped (matching semver)
• [X] If code changes were made, the yarn build command has been run and to update the cdn directory
• [X] If code changes were made, the documentation (in the /docs directory) has been updated

Resolves

Resolves #269