StdLib - Stage #1

[koczkatamas]

Epic: #9

Stage 1 - Split current libs into packages

As a first step remove standard library related entries from the language YAML files, more precisely the root > classes node.

Add a packages folder and various packages as subfolders, eg. One.Reflect-v0.1 and put a package.yaml file there with metadata and the current inline implementations (alternatively put inline implementation separately). Also put language-specific files there (eg. One.Reflect.cs).

It would be good if the WebIDE could download multiple files at once, so we don't have to execute thousands of requests. Conveniently it could be a JSON payload generated at a publish step (for now) + an endpoint on static serve.

In this stage we just concatenate the various StdLib parts into one file (order matters for eg. C++!).

Interfaces and implementations maybe should be already separated at this point already (but still without tests).