Mostly planning changes, nothing real functional but I want to commit and change
computers.
Bu::Uuid now supports being formatted, it uses the standard toString() method.

The new cache is really coming along now.
The new caching system is almost there.  It's more elaborate internally, and
it works very, very differently, but the interface is proving much easier to
use and it should be much faster, not to mention thread-safe.
Added bind/unbind to the Cache system.  Fixed typo in docs of heap.
The new cache system is tested and ready, it just needs to be put in it's place.

The old cache system will be going away now, so if you need it for anything,
grab a version before this commit.

Oh, also, happy 1,000th commit!
The new cache system has been broken out into it's individual headers, and is
now ready for actual use.
Corrected compliation issue in the new cache with older GCC versions.
Added the has function to the new cache system.  If the object identified by
key is loaded then the query doesn't even get to the superclass.
Cache object handles changed() events when no cache has been set cleanly now.
The Bu::MyriadCache now ensures that it saves the myriad structure after
saving an entry or syncing.
Corrected a pure virtual call issue while destroying caches.