Update ClientScreenWidthComparison.cs

Settings.GetSetting was referencing the wrong setting name. Was "cookieName" but should be "RDR_cookieName" to match the config file. Thanks!
Fixed to not do resolver processing when in page editor mode, depending on rules set and layouts present (or not present) this can cause a redirect loop when Page Editor is launched.
Merge pull request #1 from ActiveCommerce/PageEditorFriendly

Page editor friendly