Stub out code that 2.11 (correctly) rejects

Not sure how to cast my way around this one, but there
must be a way.
Refactor code to work around macro-paradise bug.

  https://github.com/scalamacros/paradise/issues/7

Also of great interest is how paradise, included only in
specs-matchers-extra, is leaking into the compilers of other
sub-projects.