Update default min-logr for improved CNV deletion detection

Author: Lenbok

src/com/rtg/launcher/globals/CoreGlobalFlags.java

@@ -192,7 +192,7 @@ public void registerFlags() {
     registerFlag(SV_IGNORE_RGSTATS_VERSION);
     registerFlag(SV_DISCORD_DEBUG_PER_RECORD);
 
-    registerFlag(SEGMENT_MIN_LOG_RATIO, Double.class, Double.NEGATIVE_INFINITY);
+    registerFlag(SEGMENT_MIN_LOG_RATIO, Double.class, -6.0);
 
     registerFlag(COVERAGE_DP, Integer.class, 2);