add 3 SplitRepeat TestCases and fix the PositionListWitable: UnionUpdate HashSet
diff --git a/genomix/genomix-hyracks/src/test/resources/data/lastesttest/MidSplitRepeat.txt b/genomix/genomix-hyracks/src/test/resources/data/lastesttest/MidSplitRepeat.txt
new file mode 100644
index 0000000..e934e54
--- /dev/null
+++ b/genomix/genomix-hyracks/src/test/resources/data/lastesttest/MidSplitRepeat.txt
@@ -0,0 +1,3 @@
+1	AGCCA
+2	CGCCT
+3	GCCGG