Daqd update, serve data from circular buffers before going to disk if possible.

Update the daqd to server requests with absolute gps times from the circular buffer if it is available before going to disk.

Previously this was done the other way, if an absolute gps time was specified the request was sent to disk and then the remainder was sent from memory, which opens up requests to errors in setting up the command for the nds server or issues on the nds process as well.

This request also has a number of other code cleanups that were done to make the code leading up to this operation easier to understand and maintain in the future.