Unify Chisel2 and chisel3 directionality (backport #2634) (#2837)

* Unify Chisel2 and chisel3 directionality (#2634)

Co-authored-by: Jack Koenig <koenig@sifive.com>
(cherry picked from commit 1aea4ef9

)

# Conflicts:
#	core/src/main/scala/chisel3/Aggregate.scala
#	core/src/main/scala/chisel3/Module.scala
#	src/test/scala/chiselTests/Direction.scala

* fix up backport

* fix up backport

* clean up diff

* make test order like it was on master

Co-authored-by: Adam Izraelevitz <adam.izraelevitz@sifive.com>
Co-authored-by: Megan Wachs <megan@sifive.com>