feat(CommandInteraction): make options a collection

[iShibi]

Please describe the changes this PR makes and why it should be merged:

Currently, CommandInteraction#options is an Array. This PR changes it to a Collection. As discussed in the support server, options of a CommandInteraction have unique names. Thus, having a Collection with names as keys is much better than using an array in this case.

Status and versioning classification:

• Code changes have been tested against the Discord API, or there are no code changes
• I know how to update typings and have done so, or typings don't need updating
• This PR changes the library's interface (methods or parameters added)
• This PR includes breaking changes (methods removed or renamed, parameters moved or removed)

[iCrawl]

This needs a rebase.

[kyranet]

As long as V8 doesn't make a random change that makes Map behave like an unordered hash map (thus not preserving the insertion order), this is fine.

The options are send in order as you'd expect them, so i appreciate the array here
Source

Other than that, LGTM.