Drop Quiltflower and upgrade to Vineflower that is the replacement

[RoiSoleil]

Fix #99

[RoiSoleil]

@jpstotz Could you review my PR ?

[jpstotz]

Thanks for the PR. I noticed that you included the whole Vineflower JAR file, exactly as it was done with Quiltflower.

On the long run I would try to get away from this way of adding external libraries in ECD (where possible). Since I added Quiltflower I found a way that seem to work better as it just uses Maven to download the official artifact and place it in the lib folder.

As an example please see how I implemented it for Fernflower https://github.com/ecd-plugin/ecd/blob/master/org.sf.feeling.decompiler/pom.xml

As Vineflower provides their artifacts via Maven central I would also prefer to reference only this artifact instead of including it into the ecd git repo.

Could you please see if you can adapt this way in your PR for Vineflower?

[RoiSoleil]

This is done ;)

[jpstotz]

@RoiSoleil Thanks for providing the PR.