Nitpicker

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* Fix format error in 'check' command (flipback)

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* 16 Fix encoding error on the validation stage (flipback)

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* Add flag --only for 'run' command (flipback)
* Add command 'validate' to check format of all the test on QA directory (flipback)
* 11 Fix validation error in command list (flipback)
* Nitpicker can be run as a command (`nitpicker` instead of `python -m nitpicker) (flipback)

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* 3 Command 'check --all-runs-passed' checks if all of the last runs are passed (flipback)
* 3 Command 'check --has-new-runs' checks if there are some new runs in the feature branch (flipback)

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* 6 Fix output of command 'list' (flipback)
* 2 Command 'add' gets user name and email from Git repo (flipback)
* 8 Fix error of utf-8 encoding in command 'add' (Rumpelshtinskiy)
* Make format of test cases more friendly (flipback):

.. code-block:: yaml

description: Some test to test something
author:
email:
tags:
setup:
- Do something
teardown:
- Do something
steps:
- Some action => Some expectation
- Some action => Some expectation

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* Fix UTF-8 bug in YAML dumping (flipback)