0ad680f7

By: Tom Sydney Kerckhove <syd@cs-syd.eu>

Normalize LF-only line endings to CRLF as a fixable error

Many iCal producers serve files with LF line endings instead of CRLF
as required by RFC 5545. Detect this and normalize to CRLF in lenient
mode, emitting LFOnlyLineEndingsFixableError.