windows: add console input api

[aymanbagabas]

This adds multiple functions to read, count, and discard console input events. Using ReadConsoleInput instead of ReadConsole or ReadFile is necessary to capture extended events such as window resize, focus, and extended key and mouse events.

This also define console event types and structs.

[gopherbot]

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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Please don’t reply on this GitHub thread. Visit golang.org/cl/621515.
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[gopherbot]

Message from Ayman Bagabas:

Patch Set 1:

(1 comment)

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After addressing review feedback, remember to publish your drafts!

[gopherbot]

This PR (HEAD: 2f88dfd) has been imported to Gerrit for code review.

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