Now, when the user clicks on a tab in the DataViewport, the corresponding Editor becomes
active. Likewise, when the user selects an Editor with a Visualizer, the corresponding
tab becomes active in the DataViewport.

Channel selection now takes place within a slick new interface. It's not
yet tied to actually changing parameters, but things should be much simpler
code-wise, as well as visually.

The AudioComponent now closes the audio device when it's not in use,
saving CPU cycles. Previously, background CPU levels would be between
8 and 10%. Now, when acquisition is not active (and audio device settings
are not being actively edited), background CPU levels drop to 2%. More
optimization will be necessary to get it down to zero, but 2% is still
a big improvement over what we had previously.

UIComponent, ProcessorGraph, etc. were still referencing the configuration
class (but not using it). Those references have now been removed, as the
configuration object will be replaced by a set of parameter and channel
objects.

Whenever files are needed for recording, the RecordNode opens them. When
they are no longer necessary (either recording has stopped, or recording
of a particular channel has stopped), the RecordNode closes them.

If continuous channels are toggled for recording within their respective editors,
a "writeContinuousBuffer" function will be activated within the RecordNode. This
function doesn't do anything yet, but it will make it easy to add diskwriting
capabilities in the near future. Once a stable format for events has been established,
a similar function will be implemented for writing event buffers to disk.