Revert "Extract System.DateTime class and related (#7)"

GitVersion.yml

@@ -9,7 +9,7 @@ patch-version-bump-message: '\+semver:\s?(fix|patch)'
 commit-message-incrementing: MergeMessageOnly
 branches:
   master:
-    mode:  ContinuousDelivery
+    mode: ContinuousDelivery
     tag:
     increment: Patch
     prevent-increment-of-merged-branch-version: true

source/CoreLibrary.nfproj

@@ -83,6 +83,8 @@
     <Compile Include="System\Collections\Stack.cs" />
     <Compile Include="System\ComponentModel\EditorBrowsableAttribute.cs" />
     <Compile Include="System\Convert.cs" />
+    <Compile Include="System\DateTime.cs" />
+    <Compile Include="System\DayOfWeek.cs" />
     <Compile Include="System\DBNull.cs" />
     <Compile Include="System\Decimal.cs" />
     <Compile Include="System\Delegate.cs" />
@@ -96,6 +98,8 @@
     <Compile Include="System\FlagsAttribute.cs" />
     <Compile Include="System\GC.cs" />
     <Compile Include="System\Globalization\CultureInfo.cs" />
+    <Compile Include="System\Globalization\DateTimeFormat.cs" />
+    <Compile Include="System\Globalization\DateTimeFormatInfo.cs" />
     <Compile Include="System\Globalization\NumberFormatInfo.cs" />
     <Compile Include="System\Guid.cs" />
     <Compile Include="System\IAsyncResult.cs" />

source/System/DayOfWeek.cs

@@ -0,0 +1,44 @@
+//
+// Copyright (c) 2017 The nanoFramework project contributors
+// Portions Copyright (c) Microsoft Corporation.  All rights reserved.
+// See LICENSE file in the project root for full license information.
+//
+
+namespace System
+{
+    /// <summary>
+    /// Specifies the day of the week.
+    /// </summary>
+    [Serializable]
+    public enum DayOfWeek
+    {
+        /// <summary>
+        /// Indicates Sunday
+        /// </summary>
+        Sunday = 0,
+        /// <summary>
+        /// Indicates Monday
+        /// </summary>
+        Monday = 1,
+        /// <summary>
+        /// Indicates Tuesday
+        /// </summary>
+        Tuesday = 2,
+        /// <summary>
+        /// Indicates Wednesday
+        /// </summary>
+        Wednesday = 3,
+        /// <summary>
+        /// Indicates Thursday
+        /// </summary>
+        Thursday = 4,
+        /// <summary>
+        /// Indicates Friday
+        /// </summary>
+        Friday = 5,
+        /// <summary>
+        /// Indicates Saturday
+        /// </summary>
+        Saturday = 6,
+    }
+}

source/System/Globalization/CultureInfo.cs

@@ -17,6 +17,7 @@ namespace System.Globalization
     public class CultureInfo /*: ICloneable , IFormatProvider*/
     {
         internal NumberFormatInfo _numInfo = null;
+        internal DateTimeFormatInfo _dateTimeInfo = null;
         internal string _cultureInfoName = "";
         internal string _name = null;
         [NonSerialized]
@@ -138,5 +139,19 @@ public virtual NumberFormatInfo NumberFormat
                 return _numInfo;
             }
         }
+
+        /// <summary>
+        /// Gets a DateTimeFormatInfo that defines the culturally appropriate format of displaying dates and times.
+        /// </summary>
+        /// <value>A DateTimeFormatInfo that defines the culturally appropriate format of displaying dates and times.</value>
+        public virtual DateTimeFormatInfo DateTimeFormat
+        {
+            get
+            {
+                if (_dateTimeInfo == null) _dateTimeInfo = new DateTimeFormatInfo(this);
+
+                return _dateTimeInfo;
+            }
+        }
     }
 }