WIP: New build email.
Fix tests, improve email details.
Use assets host for email images.
Delete old build email files.
Use https for assets.
Add url_options.
Specify proper URLs for img elements.
Style link in the build email header.
Fix styles to be more specific.
More email style fixes.
Lawl, email?
Set a proper width for the footer.
Fix footer width.
Remove separate centering for small footer.
Fix changeset arrow.
Link IRC channel.
Inline images into img tags.

Gmail hates background images.
More styling fixes.
Fix size for build status icon.
Add default avatars.