Move code to be more OO

[fboucher]

In UrlShortener.cs around line 109 the cleaning should be inside the object ShortUrlEntity

            string longUrl = input.Url.Trim();
            string vanity = string.IsNullOrWhiteSpace(input.Vanity) ? "" : input.Vanity.Trim();
            string title = string.IsNullOrWhiteSpace(input.Title) ? "" : input.Title.Trim();

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[ananta]

@FBoucher,

I think this one needs some love. Can I work on this one :) ?!