Support for js based locales

[stevelacey]

I switched my locale files from js to json to get the benefits of this package, there are still gaps though, for example, I build some translations dynamically out of the main set, which means I am now seeing erroneous no-missing-keys warnings, it'd be great to be able to use js-based locales

[stevelacey]

After a few months the translations started to get unwieldy, so I've now broken them up into multiple json files that I stitch together with path-based rules for vue-i18n, and again I'm running into issues here, it'd be great there was an ability to supply a messages object ala vue-i18n so that I could thus construct it however I want and feed it into this plugin.

[fairking]

Also would be nice to have typescript resources (strong type):
and something like: $t(r => r.My.Resource.MyString) with IntelliSense and type check.

[jagged3dge]

I'm looking for support for .TS based locales. That's just one step farther from js based locales.

[krausvo1]

Also looking for support for locales in *.ts files. It took me a while to realize it's not supported yet (mainly thanks to this issue), perhaps a sentence or two in documentation mentioning supported file types for locales might be helpful for future users.