Buffer Lib does not transpile code into ES2015 which does not allow to import it by older devices

[vvasylkovskyi]

On our project, we faced an issue of having a non-tranpiled const in node_modules. This is an issue for us as some of the devices we support end up not working due to a transpilation error.

As a fix on our side, we have to fork buffer lib locally and transpile it ourselves so that all const become var and other ES2015 syntax (we are also a lib used by the apps, so transpiling buffer code via webpack was not an option).

Is it possible to solve it on the buffer side and compile contents to ES2015 so we can import buffer again?

[vvasylkovskyi]

I have a fix PR for that, adding build options and a tsconfig.json file, but I have to privileges to push to the repo. I would be happy to push it if possible