Convert project to .net standard 2.0, and add a bunch of new things

[Kaydax]

I converted the project over to .net standard 2.0 as its a library, so its better to make it easy to be used cross platform without any issues.

I also found parsing issues that I fixed, tested in 20.6+ of FL Studio, should work for older versions (hopefully)

• Added mode parsing on automation key frames
• Added enums for keyframe modes
• Fixed tempo parsing for 20.6+
• Added support for muted patterns
• Added support for Echo
• Added in note color parsing
• Fixed parsing mistakes that could have caused problems
• Fixed maxTrackCount being wrong even though flp is version 20+
• Removed sanity check of file size, because trust me.... there are big flps out there

If there is any issues just let me know, these are just changes I have made for my own use case, and just wanted to share my findings and fixes