v1.6.0

Features

• when: add then_do API for triggering a callback (#39) (01fb271), closes #31
• add mock method to replace create_decoy, create_decoy_func (#37) (d3e0ae9)
• spy: add inspect.signature and repr support (#35) (0b12237), closes #29 #30
• warnings: add RedundantVerifyWarning (#36) (633159f), closes #34