better signal handling

[poelzi]

i extended the cassandra bindings with more save signals.

while tesitng a ran into some state bugs, mostly related tho columnfamilies not beeing ready and unsave signaling on the client as well. i fixed it with a more useable event system allowing easy callbacks in test environments.

for some reason i havent found out why expresso is doing this: the test suite runs trough the tests successfully, but waits for some reason and will not finish. ctrl + c prints: 100% success.... some callback seems to cause stall, on my projects using vows, everything works nice.

in my uuid branch i extended the bindings with transparent handling of uuid objects, making them easier to use then binary strings.

[rstacruz]

+1