Use OpenSSL for Base64 encode and decode

This hint came in handy today...

http://www.macosxhints.com/article.php?story=20030721010526390

To decode from Base64:

openssl base64 -d -in <infile> -out <outfile>

Conversely, to encode to Base64:

openssl base64 -in <infile> -out <outfile>