Add Env Var to disable second level cache

This is an attempt to track down possible causes of remaining database lockups. Add an environment variable to disable the second-level cache entirely to see if it works better on systems that still experience lockups.

Signed-off-by: gnattu <gnattuoc@me.com>

Emby.Server.Implementations/ConfigurationOptions.cs

@@ -19,7 +19,8 @@ namespace Emby.Server.Implementations
             { FfmpegAnalyzeDurationKey, "200M" },
             { PlaylistsAllowDuplicatesKey, bool.FalseString },
             { BindToUnixSocketKey, bool.FalseString },
-            { SqliteCacheSizeKey, "20000" }
+            { SqliteCacheSizeKey, "20000" },
+            { SqliteDisableSecondLevelCacheKey, bool.FalseString }
         };
     }
 }