[IPHONEAPP-684] Calendar object caching
[IPHONEAPP-684] Calendar object caching

Don't cache calendars like this; they are not updated and will eventually become stale. Instead, use CFCalendarCopyCurrent. It's toll-free bridged and is documented to returned a cached calendar if there is one available.

Signed-off-by: Blake Skinner <f2809f73afc906ecbb5ce29ea24012b18700bcc7@mit.edu>

xNUTs/MIT-Mobile-for-iOS,smartcop/MIT-Mobile-for-iOS,MIT-Mobile/MIT-Mobile-for-iOS,smartcop/MIT-Mobile-for-iOS,MIT-Mobile/MIT-Mobile-for-iOS,xNUTs/MIT-Mobile-for-iOS