I used to like keeping whitespace on blank lines that lined up with the
indentiation level of the code. I don't like doing that any more, so out it goes.

User oskar_calvo discovered that if you update Date iCal from 1.x, but
don't also install the Libraries module, you'll get a fatal error when Date iCal
attempts to check for the iCalcreator library, because the libraries_detect()
function doesn't exist.

Now, you'll instead see an error in the site requirements.

The update hook now also checks for importers which are set to the new parser,
but still have un-capitalized source keys. This will help users who forget to
run the database update before manually fixing the missing
DateIcalIcalcreatorParser warning.

This commit adds the migration code that converts all Feeds Importers which used
the DateIcalIcalcreatorParser plugin to use DateiCalFeedsImporter instead. The
old classes have been removed.

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.

Includes patches from issues 1895396 and 1462646.
Updated the README and the CHANGELOG.