Updated JavaMail dependency to use a specific version.
Set Javamail dependency version to 1.5.2 - latest version of Javamail as of 10/2014.
Added static method GreenMailUtil.sendMimeMessage to allow MimeMessage constructed emails to be sent through GreenMail
Added a test to GreenMailUtilTest to verify a bad envelope being generated when IMAP messages with message-id's that have unescaped characters are fetched. See https://github.com/greenmail-mail-test/greenmail/issues/4 for more details.