Calendar week view should merge some conflicts

[thatoddmailbox]

For example, if you have events like so:

The current week view logic groups all of those events, since they all overlap with at least one other event in the group. While it's technically correct, we're not taking advantage of all the space available. In that example, the 6.002 and 6.02 events don't overlap with each other, and so those two columns could be merged together. (in other words: we only really need to split those three events into two columns)