README tidy - fixing whitespace, typos and grammar
Switch tests to pytest
Remove use of unittest.TestCase
Add simple tests to ensure patterns are saved correctly
Add an easy way to run tests, and document it
Generate HTML coverage reports when running make coverage
Renaming a test file for clarity
Fixing typo: defaut -> default
Add some tests for the occurrences and count methods
Improve redundant test name
Exhaustive tests for to_weekday
Check occurrences for inclusion dates in addition to patterns
Check occurrences for exclusion dates and patterns
Try saving a variety of invalid objects, and ensure we fail
Add tests for the until kwarg for rules, and tests for after/before
Add tests to show what the Weekday object does
Adding a note about potentially dead code
Check a few more ways in which rules can be invalid
Test and bugfix for invalid bymonth recurrence

Previously this would cause a TypeError, because of invalid
string formatting.
Add another comment about potentially dead code