add option to propogate_errors

[wjwatkinson]

Description

Give users the option to have their tasks operate like the rest of Ruby and have all errors, including StandardError, raised without explicitly having to wait, or call result.

Types of Changes

• New feature.

Testing

• [x] I added tests for my changes.
• [ ] I tested my changes locally.
• [ ] I tested my changes in staging.
• [ ] I tested my changes in production.