Today, $currentDate in update command has several issues:

1. Passing in 'false' instead of 'true' keeps the type as date. If this is intended, it should be documented.
   1. Should it accept 1 and 0 as boolean? I would argue against that due do the following...
2. $type field does not take in typeId like how $type query operator does today.
3. Shapifying $currentDate always results in something like: 
   example: { $type: "date" }, regardless of whether boolean or string is used. If we want to gather more info on cx usage (especially to gather data for point 1), then it should be shapified to be exactly like how the cx uses $currentDate.