Start v0.12.2-dev
Do not export case and receive vars
Reenable case clause rewriting, closes #1972
Ensure bitstring modifiers args are expanded
include in ExUnit only has effect after an exclude
Support @moduletag in ExUnit
Fix spelling of overridden
Only run setup_all if there are tests in the case
Update CHANGELOG
Ensure teardown test case is returned
Format lock opts with the lock

This is a simpler solution to the problem outlines on issue #1879
Improve stacktraces and error messages during expansion
Deprecate is_alive in favor of Node.alive?
Compile with relative paths and include apps in stacktraces

Closes #1964, closes #1861
Use relative paths when compiling elixir itself
Annotated types should not be in guard vars
Use :application.get_application/1 in stracktraces
Create a signature for callbacks
Fixing doc typos in ExUnit
Fixing doc typos in Kernel.Typespec