Tests whether this object is equal to the given object.

The equals method should have the following properties for any non-null IEquatable objects x, y, and z:

• x.equals(null) should return false.
• It is symmetric: x.equals(x) should return true.
• It is reflexive: x.equals(y) should return true if and only if y.equals(x) returns true.
• It is transitive: if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
• It is consistent: multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.