[Chandler-dev] Don't import events more than 1 month old

[Mimi Yin]

Is it worth providing an import option to calendar users where they  
can choose to only import their calendar starting from 1 month ago?

The theory is that it usually takes a while for users to build up to  
hundreds of events and tasks in their task lists and calendars.  
However, when people import existing calendars, they bring with them  
a potentially huge number of past events that they arguably don't  
need easy access to anymore? (This problem compounds when people  
start subscribing to share each other's calendars.)

Could we potentially lower the bar for # of items we need to  
accommodate in Preview by offering this option?

Also, does this give us a performance boost if the calendar is mostly  
recurring events?

Mimi