Switchboard

- drop support for python 2
- drop support for pymongo 2.* versions
- add support for python 3.8 - 3.10
- Default to not allow connection failures

Development
- switch from nose to pytest
- constrain pymongo version to < 4
- switch from Travis to GitHub Actions
- show README contents on PyPI
- testing fixes

Small optimizations:
- cache compiled Regex patterns
- running Webob.path (hasattr will execute a `property`) is expensive, so don't
check it. Tried using dir() instead, but its even slower overall
- microoptimization: avoid tuple(sorted(.. when empty kwargs (common)

- Fix `hasattr` py2/py3 behavior issue

* 64 Python 3 fix when caching is in use

- cherry-picked commits from master to maintain good test coverage on this 1.x branch, and also keep consistency with master as much as possible. Many conflicts dealt with, and pymongo->datastore changes were omitted.
- test fixups
- 33 support newer pymongo
- 60 python 3 updates
- improvement + test coverage for a change back in kyle's Coverage commits (discovered when testing with a real app "sfpy")

- [52] Speedups via internal improvements and result caching option