Add support for strictPluralKeys MessageFormat option

[jaideepsingh]

Issue #102

With reference to the above issue, a default true option strictPluralKeys was added to @messageformat/core package.

This change adds support for that option.

[jaideepsingh]

@lephyrus May I request a review here please? Many thanks 🙏

[lephyrus]

@jaideepsingh Thanks for the PR! Prettier is complaining about some of the formatting, and could you add the new strictPluralKeys config option to the corresponding code block in the README where all the config options and their defaults are listed? Once that's done, I'll be happy to merge and release a new version.

[jaideepsingh]

@jaideepsingh Thanks for the PR! Prettier is complaining about some of the formatting, and could you add the new strictPluralKeys config option to the corresponding code block in the README where all the config options and their defaults are listed? Once that's done, I'll be happy to merge and release a new version.

@lephyrus Thank you for the feedback. I have updated the PR with your suggestions. Please take a look whenever you can.

[jaideepsingh]

@lephyrus Apologies for bothering you again. Just wanted to follow up on this one if you had a chance to take a look at this yet. This update is critical for our team as it is blocking migrating our apps to Angular 15 and subsequent versions. I would greatly appreciate any time you could spare to review this. Many thanks in advance 🙏

[lephyrus]

This is now available in version 6.5.0. Thanks again for your contribution.