AlphaTab should be available on node.js

[Danielku15]

Expected Results

Using alphaTab within node.js should be possible without errors.

Observed Results

Due to some strong dependencies to the browser in the JS version, you run into errors with alphaTab.

Steps to Reproduce

See #541

Further details

The main API object is not to use, but the low level APIs are platform independent enough to support this. A property in the Environment class should provide the runtime environment (browser, node or webworker). Then we can handle the corresponding checks at the required places.

Your environment

Version

• 1.0
• 1.1
• 1.3-alpha.##

Flavor

• JavaScript
• .net

System
Node.js LTS 14.15.4 on Windows 10