Implement method SeparateByEqualParts() for separating list of elements to equal parts

[Tim55667757]

Example:

SeparateByEqualParts(elements=[1, 2, 3, 4, 5, 6, 7, 8, 9, 10], parts=2) -> [[1, 2, 3, 4, 5], [6, 7, 8, 9, 10]]
SeparateByEqualParts(elements=[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10], parts=2, union=True) -> [[0, 1, 2, 3, 4], [5, 6, 7, 8, 9, 10]]
SeparateByEqualParts(elements=[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10], parts=2, union=False) -> [[0, 1, 2, 3, 4], [5, 6, 7, 8, 9], [10]]]

[Tim55667757]

Implemented since v 1.6.dev132

Debug build: https://app.travis-ci.com/github/Tim55667757/TKSBrokerAPI/builds/258459235
Artefact in PyPI for testing: https://pypi.org/project/tksbrokerapi/1.6.dev132/