updating the presentation of proofs and theories.

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

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

src/main/scala/proven/ElementsOfSetTheory.scala

src/main/scala/proven/dev/MainLibrary.scala

src/main/scala/proven/dev/SetTheory.scala

src/main/scala/utilities/KernelHelpers.scala

src/main/scala/utilities/TheoriesHelpers.scala