Add scale function for polynomial resources.

contrib/src/main/java/gov/nasa/jpl/aerie/contrib/streamline/modeling/polynomial/PolynomialResources.java

@@ -282,6 +282,10 @@ public static Resource<Polynomial> negate(Resource<Polynomial> p) {
     return result;
   }
 
+  public static Resource<Polynomial> scale(Resource<Polynomial> p, double scalar) {
+    return multiply(p, constant(scalar));
+  }
+
   /**
    * Multiply polynomial resources.
    */