Use BouncyCastle's MD5 implementation unless we are building w/o BouncyCastle support
Use BouncyCastle's MD5 implementation unless we are building w/o BouncyCastle support

Another step toward PCLification.

jstedfast/MimeKit,nachocove/MimeKit,nachocove/MimeKit,jstedfast/MimeKit,jstedfast/MimeKit,nachocove/MimeKit