A very fast and memory efficient class to encode and decode to and from BASE64 in full accordance
with RFC 2045.
On Windows XP sp1 with 1.4.2_04 and later ;), this encoder and decoder is about 10 times faster
on small arrays (10 - 1000 bytes) and 2-3 times as fast on larger arrays (10000 - 1000000 bytes)
compared to sun.misc.Encoder()/Decoder().
On byte arrays the encoder is about 20% faster than Jakarta Commons Base64 Codec for encode and
about 50% faster for decoding large arrays.