Add ToString and comparison operators to ByteRate with tests

[Cirzen]

Fixes #802

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• Run either build.cmd or build.ps1 and ensure there are no test failures

[dnfclas]

All CLA requirements met.

[Cirzen]

Looks like my typo correction has caused one of the tests to fail. I'll revert that change.

[Cirzen]

Failing on the approve_public_api test, since that's what I've changed.
Was

    public class ByteRate
    {
        public ByteRate(Humanizer.Bytes.ByteSize size, System.TimeSpan interval) { }
        public System.TimeSpan Interval { get; }
        public Humanizer.Bytes.ByteSize Size { get; }
        public string Humanize(Humanizer.Localisation.TimeUnit timeUnit = 1) { }
        public string Humanize(string format, Humanizer.Localisation.TimeUnit timeUnit = 1) { }
    }

Now

    public class ByteRate : System.IComparable, System.IComparable<Humanizer.Bytes.ByteRate>, System.IEquatable<Humanizer.Bytes.ByteRate>
    {
        public ByteRate(Humanizer.Bytes.ByteSize size, System.TimeSpan interval) { }
        public System.TimeSpan Interval { get; }
        public Humanizer.Bytes.ByteSize Size { get; }
        public int CompareTo(Humanizer.Bytes.ByteRate other) { }
        public int CompareTo(object obj) { }
        public bool Equals(Humanizer.Bytes.ByteRate other) { }
        public string Humanize(Humanizer.Localisation.TimeUnit timeUnit = 1) { }
        public string Humanize(string format, Humanizer.Localisation.TimeUnit timeUnit = 1) { }
        public override string ToString() { }
        public string ToString(string format, Humanizer.Localisation.TimeUnit timeUnit = 1) { }
    }

Could do with some feedback or guidance on best way to proceed here.

[AKTheKnight]

If you run either build.cmd or build.ps1 it should come up with a method of updating the PublicApiApprovalTest.approve_public_api.approved.txt file.

Once that matches the public api, the test will then pass

[Cirzen]

Hi Claire, would you be willing to have another look at this, I've hopefully resolved any remaining concerns.

[clairernovotny]

Looks like there's a build error that needs to be resolved?

[Cirzen]

You're right, I jumped the gun. Looks like some issues in Master

[Cirzen]

Now passing tests

[SimonCropp]

@Cirzen sorry for the delay. can you rebase and re-approve the api changes