Publish.WinForms: Extracted logic from wizard to FeedBuilder

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rename : src/Publish.WinForms/Wizards/WindowsIconPage.Designer.cs => src/Publish.WinForms/Wizards/IconPage.Designer.cs
rename : src/Publish.WinForms/Wizards/WindowsIconPage.cs => src/Publish.WinForms/Wizards/IconPage.cs
rename : src/Publish.WinForms/Wizards/WindowsIconPage.resx => src/Publish.WinForms/Wizards/IconPage.resx