Version 0.15.1

Bugfixes

• Fixes dataclasses import, it was failing on python3.6
• Fixes InconsistentComprehensionViolation work with async comprehensions
• Fixes nested compehensions support for InconsistentComprehensionViolation
• Fixes multiple if support for InconsistentComprehensionViolation
• Fixes that NestedTernaryViolation was not reported for a comprehension
• Fixes that ConstantConditionViolation was not reported for a comprehension
• Fixes that ConstantConditionViolation was triggering for while x := True:
• Fixes that UselessElseViolation was not reported
  for for, while, and try keywords
• Fixes false positive InfiniteWhileLoopViolation for try #1857
• Fixes that InfiniteWhileLoopViolation was not triggered on 1
  or other truthy nodes

Misc

• Refactors how tokenize tests are executed,
  now we have an option to compile fixture code
  to make sure it is syntatically valid