Deprecate moment().min/max
Implement moment.min and moment.max
Tests for moment.min/max
Add issue link in deprecation message
Fix weekyear/week creation

Initializing a moment given weekyear/week/weekday was not correct for years
starting on Monday.
Refactor week initialization
Make jshint happy
Better dfl implementation
Mark human weekday as invalid when parsing
Extract argument handling logic in pickBy
Make JSHint happy and me unhappy
Merge pull request #1641 from ichernev/fix-init-from-week

Fix init from week
Merge pull request #1637 from ichernev/min-max-redo

Min max redo
Implement accurate moment.duration({from, to})
Better bubbling of days to years in duration
Use duration object in relativeTime
internal relativeTime now accepts only duration object
Fix bugs in humanize and asYears
Fix moment tests
Fix language tests