Add screens.

Cicm.Database/Models/Screen.cs

@@ -0,0 +1,28 @@
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace Cicm.Database.Models
+{
+    public class Screen : BaseModel<int>
+    {
+        [Range(1, 131072)]
+        public double? Width { get; set; }
+        [Range(1, 131072)]
+        public double? Height { get; set; }
+        [Required]
+        public double Diagonal { get; set; }
+        [Required]
+        public virtual Resolution NativeResolution { get; set; }
+        [Range(2, 281474976710656)]
+        public long? EffectiveColors { get; set; }
+        [Required]
+        public string Type { get; set; }
+
+        [NotMapped]
+        public long? Colors => EffectiveColors ?? NativeResolution.Colors;
+
+        public virtual ICollection<ResolutionsByScreen> Resolutions       { get; set; }
+        public virtual ICollection<ScreensByMachine>    ScreensByMachines { get; set; }
+    }
+}