Change Licence names to SPDX identifier format

[ptornhult]

Several extensions here have specified licence name to be "Apache License, Version 2.0" instead of the SPDX identifier "Apache-2.0". This is causing an issue with the npm licence dependency checker package: "licence-checker" which can't exclude this licence since it has a comma in the licence name. I'm trying at both ends to fix this, but if you could change the licences to be named as per the guidelines in the documentation of npm package.json it would really help (See: https://docs.npmjs.com/files/package.json#license)

Also see: https://spdx.org/licenses/

Thank you!

[ptornhult]

I've seen this issue in rx-lite and rx-lite-aggregates but there may be other extensions as well