new support for Raspberry Pi B+

[draymond at FoxValley.net]

Quoting Luiz Otavio O Souza <lists.br at gmail.com>:

> With the patch the card is always identified with correct speed and
> bus speed, this leads to consistent failures as RPi cannot handle HS
> speed for some cards, whence the the use of hw.bcm2835.sdhci.hs="0" to
> make it work.

Thanks, Luiz.  That explains a lot.  I agree this is a move in the  
right direction but one thing to consider is that new official images  
will be unusable to many people because they won't be able to add the  
hw.bcm2835.sdhci.hs="0" hack if it consistently fails to boot.  It  
might be a good idea to embed the hack into official images until this  
gets sorted out.

Do you have any ideas on the I/O errors during the partition resize  
operation with my SanDisk 32GB?  Let me know if you want me to try  
anything else out.

Keep up the good work.  :)