Implement basic function for finding first weekday of month.
Use existing dayOfYear() in formatting.
Remove some unused functions and improve test coverage.
Implement secondOfDay() and weekOfMonth(), including tests and formatting.
Merge pull request #12 from daanwissing/master

Implement DateTime.format() functionality
Add methods to retrieve time zone abbreviation for a given date.
Add most of the formatting of timezones.
Improve test coverage, bugfix in DateTime.valueOf()
Add source maps to js files.
Refactored formatter to be just a function, and to take a TimeStruct instead of a DateTimeAccess.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	lib/datetime-interface.js
	test/test-basics.js
	timezonecomplete.v12.suo
Implement some more formatting rules for timezones.
Properly implement Z token for Zone, including tests.
Add some more defensive programming and tests in format.ts. Add comments. Update docs.