Does not run tests on Python 2

[icemac]

I stepped in the debugger through find_captures, it did not find a single region on Python 2. So no tests are run.

manuel/src/manuel/capture.py

Lines 21 to 25 in 89f3a04

	def find_captures(document):
	while True:
	regions = document.find_regions(CAPTURE_DIRECTIVE)
	if not regions:
	break

This is even visible on TravisCI (I activated verbose mode in my fork so the test names are shown):

• For Python 2.7 only 6 tests are run: https://travis-ci.com/icemac/manuel/jobs/227655144
• But for Python 3.7 60 tests are run: https://travis-ci.com/icemac/manuel/jobs/227655148

[icemac]

I digged a bit deeper into the code and found the actual problem here:

manuel/src/manuel/testing.py

Lines 183 to 189 in 89f3a04

	with io.open(abs_path, 'rt', newline=None) as fp:
	contents = fp.read()
	if not isinstance(contents, str):
	# Python 2, we read unicode, but we really need a str
	contents = str.encode("utf-8")
	document = manuel.Document(
	contents, location=abs_path)

On Python 2 the contents are always 'utf-8', see line 187.