cleanup WolfePlayground
Merge remote-tracking branch 'origin/compiler' into compiler

Conflicts:
	src/main/scala/scalapplcodefest/compiler/WolfePlayground.scala
larger code example in DummyTransformer
Merge remote-tracking branch 'origin/compiler' into compiler

Conflicts:
	src/main/scala/scalapplcodefest/compiler/WolfePlayground.scala
Merge remote-tracking branch 'origin/compiler' into compiler
local commit
Merge remote-tracking branch 'origin/compiler' into compiler

Conflicts:
	src/main/scala/scalapplcodefest/compiler/WolfeTransformer.scala
Merge remote-tracking branch 'origin/compiler' into compiler
adapted to new StringCompiler