Tests and experimentation of theory files structure, more work on dsl.

build.sbt

src/main/scala/dev/A.scala

src/main/scala/dev/WithMain.scala

src/main/scala/lisa/kernel/proof/RunningTheory.scala

src/main/scala/lisa/settheory/SetTheoryDefinitions.scala

src/main/scala/lisa/settheory/SetTheoryTGAxioms.scala

src/main/scala/lisa/settheory/SetTheoryZAxioms.scala

src/main/scala/lisa/settheory/SetTheoryZFAxioms.scala

src/main/scala/proven/DSetTheory/Part1.scala

src/main/scala/proven/MainLibrary.scala

src/main/scala/proven/SetTheory.scala

src/main/scala/utilities/Library.scala

src/main/scala/utilities/TheoriesHelpers.scala