changed expressions in term of algebraic operations with corresponding numeric results (#323)

refactored specific-energy tests

* fixed *CaloriesPerGramInOneJoulePerKilogram tests

* prettification

* refactored watthour tests

watt, kilowatt and megawatt tests should have the same number of significant figures

* prettification

ordered tests according to types and exponents

Author: gratestas

UnitsNet.Tests/CustomCode/SpecificEnergyTests.cs

@@ -25,22 +25,14 @@ namespace UnitsNet.Tests.CustomCode
 {
     public class SpecificEnergyTests : SpecificEnergyTestsBase
     {
-        protected override double JoulesPerKilogramInOneJoulePerKilogram => 1.0;
-
-        protected override double CaloriesPerGramInOneJoulePerKilogram => 1.0/4.184E3;
-
-        protected override double KilocaloriesPerGramInOneJoulePerKilogram => 1.0/4.184E6;
-
-
-        protected override double KilojoulesPerKilogramInOneJoulePerKilogram => 1.0E-3;
-
+        protected override double JoulesPerKilogramInOneJoulePerKilogram => 1e0;
+        protected override double KilojoulesPerKilogramInOneJoulePerKilogram => 1e-3;
+        protected override double MegajoulesPerKilogramInOneJoulePerKilogram => 1e-6;
+        protected override double CaloriesPerGramInOneJoulePerKilogram => 2.3900573613766730401529636711281e-4;
+        protected override double KilocaloriesPerGramInOneJoulePerKilogram => 2.3900573613766730401529636711281e-7;
+        protected override double WattHoursPerKilogramInOneJoulePerKilogram => 2.77777778e-4;
         protected override double KilowattHoursPerKilogramInOneJoulePerKilogram => 2.77777778e-7;
-
-        protected override double MegajoulesPerKilogramInOneJoulePerKilogram => 1.0E-6;
-
-        protected override double MegawattHoursPerKilogramInOneJoulePerKilogram => 2.77777778E-10;
-
-        protected override double WattHoursPerKilogramInOneJoulePerKilogram => 1.0/3.6e3;
+        protected override double MegawattHoursPerKilogramInOneJoulePerKilogram => 2.77777778e-10;
 
         [Fact]
         public void MassTimesSpecificEnergyEqualsEnergy()