Fix event pagination in month views

Summary: Closes T7927, Fix event pagination in month views.

Test Plan: Querying for events in month view should display max that month's events and min the subset of days selected.

Reviewers: Blessed Reviewers, epriestley

Reviewed By: Blessed Reviewers, epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T7927

Differential Revision: https://secure.phabricator.com/D12661