MQE-1087: Test _after hook does not run if test fails with exception

[KevinBKozan]

Description

• TestContextExtension now handles error events, and runs _after block if the test errored out.

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/verification tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)
• Changes to Framework doesn't have backward incompatible changes for tests or have related Pull Request with fixes to tests

[coveralls]

Coverage remained the same at 56.039% when pulling 2626feb on MQE-1087 into 00f473b on develop.