lib: establish py3 compatible strategy for string handling: introducing safe_bytes and deprecating safe_str The meaning of safe_str will change when moving to py3. All use of safe_str is thus tech debt that we have to chop off, mostly by moving to either safe_unicode or safe_bytes ... or dropping because we know what we are doing and rely on the improved type safety in py3.

pytest >= 4.6.6, < 4.7
pytest-sugar >= 0.9.2, < 0.10
pytest-benchmark >= 3.2.2, < 3.3
pytest-localserver >= 0.5.0, < 0.6
mock >= 3.0.0, < 3.1
Sphinx >= 1.8.0, < 1.9
WebTest >= 2.0.3, < 2.1
isort == 4.3.21