Add Exception Documentation to Helper Methods

[scottolsonjr]

To help developers implement the library methods it would be helpful to disclose the exceptions that could be returned by the method.

For example:

        /// <summary>
        /// Returns whether a <see cref="FormObject"/> exists in an <see cref="OptionObject2015"/> by <see cref="FormObject.FormId"/>.
        /// </summary>
        /// <param name="optionObject"></param>
        /// <param name="formId"></param>
        /// <exception cref="ArgumentNullException">
        /// An <see cref="ArgumentNullException"/> may be thrown if the provided <see cref="OptionObject2015"/> is null or the FormId is null or empty.
        /// </exception>
        /// <returns></returns>
        public static bool IsFormPresent(IOptionObject optionObject, string formId)

See https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/language-specification/documentation-comments#d3-recommended-tags