Add babel-plugin-transform-typescript-metadata plugin

[darbio]

Thanks for your great plugin - saves us a lot of time and effort getting things up and running.

Lots of projects use typescript metadata (e.g. tsyringe, typestack, typegoose ... to name a few).

We are trying to implement dependency injection framework tsyringe into our stack to simplify dependency resolution, and in order for this to work with babel, we have to install the babel plugin babel-plugin-transform-typescript-metadata.

Decorators especially are a highly used part of typescript so it would be good to be able to support them in this plugin.

[enchorb]

+1 this is needed for libraries like typeorm

[dpecos]

+1 typeorm does not work with esbuild enabled unless we annotate absolutely everything, which is not needed when esbuild is disabled.

esbuild not emiting metadata is the root cause for that problem, but that feature is not exposed via config.

[ricardo-cn]

+1. That'd be great.