Move to SQLite 3080600 (aka 3.8.6)

This new version of SQLite offers significant speed improvements in my testing. For example, the time it takes to issue

    SELECT * FROM tvshowview  GROUP BY tvshowview.idShow

(the first time the TV Shows library is opened) with 344 TV shows on a non-overclocked Raspberry Pi changed as follows. Times are in seconds:

          Before          After
          Mean   StdDev   Mean   StdDev  Confidence  Change
    Time  2935.6 6.2      2774.1 38.3    100.0%      +5.8%