Rethrow exception so that job status is handled

[georgebohnisch]

Closes #60

[m2jobe]

Tested and looks good

[klimov-paul]

Such change may break existing applications.
For example: Twilio client throws an exception in case of invalid receiver phone number or in case receiver phone number belongs to unsupported region.
See:

• https://www.twilio.com/docs/api/errors/21608
• https://www.twilio.com/docs/api/errors/21211
• https://www.twilio.com/docs/api/errors/21614
• https://www.twilio.com/docs/api/errors/21408

If this PR accepted Laravel application may easily end up in 500 error in case user entered incorrect phone number by a mistake.

[klimov-paul]

Enhanced solution provided via #73

[atymic]

Thanks for the PR, introduced in #90 :)