1) renamed test build type to 'debugTest' because updated gradle

plugin doesn't allow build types to start with 'test'.

2) exclude support-annotations to avoid warning

Closes #3273
// FREEBIE

src/org/thoughtcrime/securesms/database/PartDatabase.java

@@ -640,15 +640,5 @@ public class PartDatabase extends Database {
     public boolean isValid() {
       return rowId >= 0 && uniqueId >= 0;
     }
-
-    @Override
-    public boolean equals(Object object) {
-      if (!(object instanceof PartId)){
-        return false;
-      }
-
-      PartId other = (PartId) object;
-      return rowId == other.rowId && uniqueId == other.uniqueId;
-    }
   }
 }