Mixed line endings cause e-mail body length issues resulting in DKIM signature failure

[Jaybus2]

Combination of incorrect and mixed CRLF and LF line endings in sent e-mail causes body length mismatches that result in DKIM signature failures. The below patch fixes this by replacing CR and LF characters in strings with the PHP 5 predefined constant PHP_EOL.

https://gist.github.com/Jaybus2/8e5957692a927e04f966#file-opendocman-1-3-2-patch-jaybus-1-diff