Add Contains and ContainsAny extension methods for IObjectProvider<IEnumerable<TSource>>

[YevgeniyShunevych]

Add extension methods:

public static bool Contains<TSource>(
    this IObjectProvider<IEnumerable<TSource>> source,
    params TSource[] items);

public static bool Contains<TSource>(
    this IObjectProvider<IEnumerable<TSource>> source,
    IEnumerable<TSource> items);

public static bool ContainsAny<TSource>(
    this IObjectProvider<IEnumerable<TSource>> source,
    params TSource[] items);

public static bool ContainsAny<TSource>(
    this IObjectProvider<IEnumerable<TSource>> source,
    IEnumerable<TSource> items);

Usage

page.SomeInput.DomClasses.Contains("class-a", "class-b");
page.SomeInput.DomClasses.ContainsAny("disabled", "state-disabled");