Wrote a README file
Updated LogicProcessor

Finally fixed LogicProcessor. Added new logic subtype 'scaler'.
This new subtype can be used to simply count logic scaler pulses.
Upon typing 'end', LogicProcessor will print the number of counts
which were found in each logic:scaler channel.

Added .gitignore.

Started new doxygen documentation on new files.

Removed LogicWaveform and LogicStructure from Structures.h/cpp.
LogicProcessor no longer adds a logic branch to the output root
tree. Logic is typically used for counting (i.e. scalers) and the
individual hits generally do not need to be saved.

Added a new variable to TriggerStructure named 'trigger_time'.
This variable is a vector of doubles that is used to store the
raw Pixie16 time from the trigger signal.