Windows Phone 8.1 Support
Merge branch 'windows-phone-8.1'
added release note entry for Windows Phone 8.1 PR
only return 'tomorrow' if datetime is actually tomorrow

Fixes issue #254
added release note for fixing DateTime.Humanize for tomorrow
Merge branch 'fix-humanize-datetime-for-tomorrow'
releasing v1.28.0
oops - added the missing release header
Fixed the inlined contributors!
Pull changes from upstream, fix merge conflict in release notes