add content_transfer_encoding to html emails
add content_transfer_encoding to html emails

By default this is set to 7bit, and this places a limit on how long
lines can be in an email.

Since our HTML emails can have lines that are really long, the 7 bit
encoding doesn't really work. Mail clients will insert whitespace after
1000 characters, and this messes up links in the email.

There's a better explanation here:
http://stackoverflow.com/questions/25710599/content-transfer-encoding-7bit-or-8-bit

etsy/nagios-herald,etsy/nagios-herald,etsy/nagios-herald,etsy/nagios-herald