Fix "make test". Add Streem example file.
Change file extension to .strm in light of decision in issue #24.
Merge branch 'fix-make-test' of https://github.com/practicalswift/streem into practicalswift-fix-make-test
add example directory and move src/example.strm -> example/fizzbuzz.strm; #30

we should update tests more decriptive in the future.
Merge branch 'practicalswift-fix-make-test'