 BIO_ssl() is not included as of this time. This one is a
 bit more complex and should probably be added later.

 How to implement next() inline without destroying current BIO?
 Ex: $bio->next->read() currently destroys $bio??

 Need better checking on all functions that reset self->bio to
 make sure we have an actual BIO before the reassignment.

 Can't really get the accept/connect BIOs to work properly. Will
 have to investigate them further.

 Need much better handling of potentially dangerous situations 
 like the instance of reassigning self->bio.

 Finish the CBC and ECB ciphers. Right now only the first 64 bits 
 are encrypted/decrypted. Need to encrypt/decrypt 8-byte chunks.

 Write more of the tests.

 If using BIO.pm and you try to flush a CBC/ECB cipher that does 
 not encrypt in 8-byte chunks, it dies. Might want to add some 
 error checking for things like this.
