Add Timeout.InfiniteTimeSpan and Sleep(timespan)

[josesimoes]

Description

• Add Timeout.InfiniteTimeSpan
• Add Therad.Sleep overload with timespan
• Improve documentation on Thread.Sleep methods

Motivation and Context

• Required to handle Serial communication is throwing exception when no timeouts are set Home#318
• Required for other UWP APIs that use timeouts properties with TimeSpan
• Add missing Sleep overload with TimeSpan which can be handy

How Has This Been Tested?

Screenshots

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: josesimoes jose.simoes@eclo.solutions

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