Add NOTICE file for Apache license 2.0

[s1061123]

This change adds NOTICE file in repository as https://infra.apache.org/apply-license.html#new

[s1061123]

This change is trivial and no harm from software PoV, hence it will be merged in a few days. Thanks.

[coveralls]

Pull Request Test Coverage Report for Build 3664078945

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 35.928%

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Totals
Change from base Build 3649375309:	0.0%
Covered Lines:	120
Relevant Lines:	334

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💛 - Coveralls