support Spark 3.2.0 and other patch-versions

[Jolanrensen]

Currently only the latest Spark 3.x.y versions are supported.
KotlinReflection.scala is incompatible with other spark versions than its exact own.
We need to set up a plan to (probably) be able to release all versions that users might want.
I expect that say 3.2.1 and 3.2.0 will work without any code change except for the version number. 3.1.x and 3.2.y will require some code change, so we can still keep separate branches for that.

[Jolanrensen]

Also, Apache also has Scala 2.13 support for Spark, not sure if we also need to support that and all versions...

[Jolanrensen]

Yes we do and yes we will :) Was a large job but #168 is gonna take care of it all