improved qAllocator

[arrenglover]

Update:

1. class name?
2. you should be able to getNextQ() without getting the envelope/timstamp.
3. implement a new method that does scapQ() plus getNextQ() so the user doesn't need to remember to scrapqs.

[arrenglover]

We should also look at removing the double buffered list that comes from wrapping around a yarp::os::BufferedPort<> and remove the double memory allocation that comes from allocating into a bottle before decoding into a vQueue. If the vQueue is a yarp::os::PortReader/PortWriter we should be able to decode directly into the vQueue.

Design choice: make qAllocator a BufferedPort<vQueue> witch extra functions to calculate the delay in events/event time. This could be messy as we would need to extend the reading function of buffered port.
or
make qAllocator a class of its own with a standard yarp::os::Port for reading.

[arrenglover]

new classes for reading and writing events on ports have been made. The ports offer a ~50% speedup over using the old ports in terms of cpu usage and delay introduced from communications.