Automatically port Char comments (EII) (#4019)

Author: carlossanlop

xml/System/Char.xml

@@ -1,4 +1,4 @@
-<Type Name="Char" FullName="System.Char">
+<Type Name="Char" FullName="System.Char">
   <TypeSignature Language="C#" Value="public struct Char : IComparable, IComparable&lt;char&gt;, IConvertible, IEquatable&lt;char&gt;" FrameworkAlternate="dotnet-uwp-10.0;net-5.0;netcore-1.0;netcore-1.1;netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netcore-3.1;netframework-2.0;netframework-3.0;netframework-3.5;netframework-4.0;netframework-4.5;netframework-4.5.1;netframework-4.5.2;netframework-4.6;netframework-4.6.1;netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netstandard-1.3;netstandard-1.4;netstandard-1.5;netstandard-1.6;netstandard-2.0;netstandard-2.1;xamarinandroid-7.1;xamarinios-10.8;xamarinmac-3.0" />
   <TypeSignature Language="ILAsm" Value=".class public sequential ansi sealed beforefieldinit char extends System.ValueType implements class System.IComparable, class System.IComparable`1&lt;char&gt;, class System.IConvertible, class System.IEquatable`1&lt;char&gt;" FrameworkAlternate="dotnet-uwp-10.0;net-5.0;netcore-1.0;netcore-1.1;netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netcore-3.1;netstandard-1.3;netstandard-1.4;netstandard-1.5;netstandard-1.6;netstandard-2.0;netstandard-2.1" />
   <TypeSignature Language="DocId" Value="T:System.Char" />
@@ -3797,10 +3797,24 @@ When a managed <xref:System.Char> type, which is represented as a Unicode UTF-16
         <Parameter Name="value" Type="System.Object" Index="0" FrameworkAlternate="dotnet-uwp-10.0;netcore-1.0;netcore-1.1;netstandard-1.0;netstandard-1.1;netstandard-1.2;netstandard-1.3;netstandard-1.4;netstandard-1.5;netstandard-1.6" />
       </Parameters>
       <Docs>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <param name="value">The object to compare.</param>
+        <summary>Compares the current instance with another object of the same type and returns an integer that indicates whether the current instance precedes, follows, or occurs in the same position in the sort order as the other object.</summary>
+        <returns>A value that indicates the relative order of the objects being compared.</returns>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Char> instance is cast to an <xref:System.IComparable> interface.
+
+| Value             | Meaning                                                                 |
+|-------------------|-------------------------------------------------------------------------|
+| Less than zero    | This instance precedes `value` in the sort order.                       |
+| Zero              | This instance occurs in the same position in the sort order as `value`. |
+| Greater than zero | This instance follows `value` in the sort order.                        |
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.IConvertible.GetTypeCode">
@@ -3830,9 +3844,17 @@ When a managed <xref:System.Char> type, which is represented as a Unicode UTF-16
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Returns the <see cref="T:System.TypeCode" /> for this instance.</summary>
+        <returns>The enumerated constant that is the <see cref="T:System.TypeCode" /> of the class or value type that implements this interface.</returns>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Char> instance is cast to an <xref:System.IConvertible> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.IConvertible.ToBoolean">
@@ -4411,10 +4433,18 @@ When a managed <xref:System.Char> type, which is represented as a Unicode UTF-16
         <Parameter Name="provider" Type="System.IFormatProvider" Index="0" FrameworkAlternate="dotnet-uwp-10.0;netcore-1.0;netcore-1.1;netstandard-1.3;netstandard-1.4;netstandard-1.5;netstandard-1.6" />
       </Parameters>
       <Docs>
-        <param name="provider">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <param name="provider">An object that supplies culture-specific formatting information.</param>
+        <summary>Converts the value of this instance to an equivalent string, using the specified culture-specific formatting information.</summary>
+        <returns>A string equivalent to the value of this instance.</returns>
+        <remarks>
+          <format type="text/markdown"><![CDATA[
+
+## Remarks
+
+ This member is an explicit interface member implementation. It can be used only when the <xref:System.Char> instance is cast to an <xref:System.IConvertible> interface.
+
+          ]]></format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.IConvertible.ToType">