PHPUnit is included using composer.
Tested in isolation using koharness.
Preparing module for Travis CI.
Disable tests for PEAR as well, it's not available on Travis CI.
Sendmail is not available as well..
Using a tagged version of PHPMailer.
Do not set the From and To headers with setting custom headers.
Strictly follows Kohana coding conventions.
Merge branch '3.3/feature/composer' into 3.4/develop

Conflicts:
	classes/Kohana/Mail/Sender/PHPMailer.php
Merge branch '3.3/master' into 3.4/develop

Conflicts:
	vendor/PHPMailer