Dev/pvs studio cleanups2 (#2877)

* a round of cleanups courtesy of PVS studio

* add a test to make sure that a warning is a false alarm

* bug fix

* Fix a UFF bug

* more PVS studio cleanups

* next round of PVS studio cleanups

* completely remove the chances for that bug

* changes in response to review

* add an additional test
+ a bit of reformatting that snuck in

Code/DataStructs/SparseIntVect.h

@@ -480,11 +480,8 @@ double DiceSimilarity(const SparseIntVect<IndexType> &v1,
     v2Sum = v2.getTotalVal(true);
     double denom = v1Sum + v2Sum;
     if (fabs(denom) < 1e-6) {
-      if (returnDistance) {
-        return 1.0;
-      } else {
-        return 0.0;
-      }
+      // no need to worry about returnDistance here
+      return 0.0;
     }
     double minV = v1Sum < v2Sum ? v1Sum : v2Sum;
     if (2. * minV / denom < bounds) {