Provide better headers and crumbs for Calendar result views
Summary:
Ref T11326. This isn't perfect, but should be a little easier to use and less weird/confusing.
Generally, provide a "Query > Month > Day" crumb on day views, and a "Wed, July 3" header.
Generally, provide a "Query > Month" crumb on month views, and a "July 2019" header.
Also try to fix a bit of padding/spacing on the day view.
Test Plan: {F1739128}
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T11326
Differential Revision: https://secure.phabricator.com/D16338