v0.9rc1: Added grammar support for issue #78

[Ari24-cb24]

Closes #78

Adds grammar support for the following testcases:

"quarter past 5pm": datetime(today.year, today.month, today.day, 17, 15, 0),
"two quarters past 5h": datetime(today.year, today.month, today.day, 17, 30, 0),
"one quarter before 10pm": datetime(today.year, today.month, today.day, 21, 45, 0),
"ten quarters after 03:01:10am": datetime(today.year, today.month, today.day, 5, 41, 10),
"hour past christmas": datetime(today.year, 12, 25, 1),
"30 minutes past easter": None