Updated to 4.0.0-m4.2, Fixed Typing with Overload for Prompt.onPrompt(), Strict, Bug Fixes

• Updated source and samples to 4.0.0-m4.2.
• Fixed issue with overload of Prompt.onPrompt() that broke the fluent API and typing.
• Turned on strict flag to find typing issues.
• Various bug fixes.

Updated to M2, Added Defaults, Overload for Prompt.onPrompt()

Notable Changes

• Updated source and samples to 4.0.0-m2.1.
• Added common sense defaults for Prompt properties (e.g. not added onPrompt will create a Prompt that doesn't write to the conversation rather than throwing).
• Added overloads for Prompt.onPrompt() so you can pass callback, string (or strings), or Activity (or Activities) to create a prompt.
• Removed all code I use for demos when showing Promptly.