LoopTest added

Verifies that XML can loop between states as long as there is a start and an end.
flashingStim works to WaitingForLever

Code stays in ITI for given time and maintains on/off periodicity waiting for lever to be pressed
Added trialStimOn/Off states; code displays stim for nCyclesOn loops
TargetStim arrives after nCyclesOn, trials tracked.
doConstantStimulus keeps stimulus from flashing.
stopITIFlashing stops ITI flashing, starts stimOn right away
Corrects error in setting tLeverPress
Sounded added and vital iti/wait/trialOn timing fixes
Updates to structure and plotting to accommodate nCycles for FlashingStim code.

Signed-off-by: Lindsey <glickfeld@neuro.duke.edu>
changed call to plotFlashingStim.m

Signed-off-by: Lindsey <glickfeld@neuro.duke.edu>
fixed hold lever timing error - LG
Working version- has outcomes- LG

Needs sounds added to end of trial, and compensation for short trials (early releases) and extra cycles added.
have extend ITI working! - LG
Added sound for extra cycles- LG
Andrew's changes to accomodate stopITIFlashing
Added early and missed TOs to ITI time
put variables in folders- LG
Plotting works
Changes to compensate for added/subtracted cycles in req hold times
Solenoids work; turn on w/ doSol__ vars, off at waitForLever