#234102 It turns out that we must always force use of the lower level date functions because regular strtotime and mktime can be off by one hour during daylight savings time.

#239900, #249399 Limit available formats for Date Popup to available formats and hide custom format code which won't work right here.

Tweak the recent changes to format interval to simplify processing and make sure they go through the right theme.

#233415 separate ical retrieval and parser so other modules like feedapi can use the parser alone, patch by ekes.

More work getting Views 2 handling working. Basic fields, filters, and arguments, including Date Browser arguments, are all working. Plugin display for the back/next Date Browser navigation is not yet added.

Temporarily adding in proposed Views patch for flexible date filters and arguments from #241759, to be removed if the patch gets into Views.

Always include content_views, remove pathauto that is not used in D6, and remove wrapper functions for content views that are not needed any more.

More work on the upgrade path to be sure all the necessary modules get enabled and that date_popup formats get adjusted to formats that work with that module.

Make sure new required modules get enabled during the update, should have made the module list an array.