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Merge pull request #172 from EricpolUkraine/test

Release merge from 'test' to 'development' (v1.11.1)
Merge pull request #173 from EricpolUkraine/development

Release v1.11.1
Removed unit test with probabilistic outcome. It can fail with low probability was needed to test if two same messages in a row appear at statistically calculated rate
Merge remote-tracking branch 'upstream/master' into development
Merge pull request #174 from Bohdan-Tereta/development

Unit test with probabilistic outcome removed
Issue #156(Edit Vacation) fixed
Merge pull request #175 from nazariitashak/development

Issue #156(Edit Vacation) fixed
Issue #176 On polish locale calendar irems and holidays on calendar are all moved one day to the left (attempt to fix, couldn't be tested or even debugged on local machine
Merge pull request #177 from Bohdan-Tereta/development

Issue #176 fix attempt
Merge pull request #178 from EricpolUkraine/development

Pre-release merge from 'development' to 'test' (v1.12.1-alpha)