Add HotKey "Ctrl + Space" for switching between Options and Compostion API (issue: #1409)

[lucaspagliari]

Description of Problem

Allow users to quickly toggle between APIs
Enhancement on user experience when reading docs.
Relates to this issue #1409

Proposed Solution

Add an event listener on window when mounting component. Implemented a handler to verify if ctrl + space or ⌘ + space were pressed. And then run toggleCompositionAPI()

Additional Information

Needs improvement to show users that this hotKey is available, but I'm open to help with that

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[skirtles-code]

@lucaspagliari I'm sorry that you didn't get a response until now. The work you did on this should have been acknowledged a long time ago. I thought someone had already responded, but that was just the netlify bot.

We have two PRs implementing #1409, the other being #1449. For various reasons that other PR hasn't been merged yet, but it is at a more advanced stage than this PR and I think we'll be merging that one relatively soon. Had that PR not already existed, I see no reason why we wouldn't have proceeded with merging this PR instead.

Sorry again for the delay and thank you for the work you put into this.