APP FUNCTIONS TO TEST and CHECK
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Last update: 10th Jan 2021

1). Launch app with setting: queue_max =  10
    (with e.g. 30 items already in the QUEUE)  
     check to see if App recovers ok.
TEST(S) PERFORMED - RESULTS = PASS


2). Play more than 11 tracks (if 10 track queue max), 
     pause for over 1 hour.
     play more tracks.
TEST(S) PERFORMED - RESULTS = PASS


3). Play a track that's NOT in QUEUE
     see what occurs..
TEST(S) PERFORMED
 RESULTS = Plays track ok, does not remove from QUEUE - but
thats OK - 
PROBLEM = Add track to end of FEEDER


4). Try playing the QUEUE with shuffle mode ON.
      a). This will allow the 30 max queue to play tracks in a different order.
      b). If successful, the said 30 tracks will be returned to the FEEDER in a
           different order, whilst still keeping them at the Least Recently Played            end of the FEEDER.
TEST(S) PERFORMED - RESULTS = PASS


5).


6).