Issue [#2018285]: Optimized the method by which the feeds parser reads data from the incoming iCal feed.

This hook allows modules to fix broken timezone strings in the iCal feeds they import.

Also cleaned up the way that timezone strings are handled by the parser, especially under error conditions.

DateIcalIcalcreatorComponent::component is no longer protected. This allows hook_feeds_after_parse() implementations to alter it.

Applied patch #11 from [#1922658] to get around iCalcreator limitation with stream wrappers. Also made the amount of whitespace on blank lines consistent throughout the project.