tidying up some docs in the Extensions namespace

Octokit/Helpers/StringExtensions.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
+using System.Net;
 using System.Reflection;
 using System.Text;
 using System.Text.RegularExpressions;
@@ -29,7 +30,7 @@ namespace Octokit
 
         public static string UriEncode(this string input)
         {
-            return System.Net.WebUtility.UrlEncode(input);
+            return WebUtility.UrlEncode(input);
         }
 
         public static string ToBase64String(this string input)

Octokit/Helpers/TwoFactorChallengeResult.cs

@@ -2,12 +2,22 @@
 
 namespace Octokit
 {
+    /// <summary>
+    /// Represents the response to a 2FA challenge from the API
+    /// </summary>
     public class TwoFactorChallengeResult
     {
+        /// <summary>
+        /// Helper action for resending the 2FA code
+        /// </summary>
         [SuppressMessage("Microsoft.Security", "CA2104:DoNotDeclareReadOnlyMutableReferenceTypes",
             Justification = "It really is immutable yo!")]
         public static readonly TwoFactorChallengeResult RequestResendCode = new TwoFactorChallengeResult(null, true);
 
+        /// <summary>
+        /// Construct an instance of TwoFactorChallengeResult
+        /// </summary>
+        /// <param name="authenticationCode"></param>
         public TwoFactorChallengeResult(string authenticationCode)
             : this(authenticationCode, false)
         {
@@ -20,8 +30,14 @@ namespace Octokit
             ResendCodeRequested = resendCodeRequested;
         }
 
+        /// <summary>
+        /// True if this request should resent an authentication code
+        /// </summary>
         public bool ResendCodeRequested { get; private set; }
 
+        /// <summary>
+        /// The user-specified authentication code
+        /// </summary>
         public string AuthenticationCode { get; private set; }
     }
 }

Octokit/Helpers/UnixTimeStampExtensions.cs

@@ -2,13 +2,21 @@
 
 namespace Octokit.Helpers
 {
+    /// <summary>
+    /// Extensions for converting between different time representations
+    /// </summary>
     public static class UnixTimestampExtensions
-    {
-        const long _unixEpochTicks = 621355968000000000; // Unix Epoch is January 1, 1970 00:00 -0:00
-        
+    { 
+        // Unix Epoch is January 1, 1970 00:00 -0:00
+        const long unixEpochTicks = 621355968000000000;
+
+        /// <summary>
+        /// Convert a Unix tick to a <see cref="DateTimeOffset"/> with UTC offset
+        /// </summary>
+        /// <param name="unixTime">UTC tick</param>
         public static DateTimeOffset FromUnixTime(this long unixTime)
         {
-            return new DateTimeOffset(unixTime * TimeSpan.TicksPerSecond + _unixEpochTicks, TimeSpan.Zero);
+            return new DateTimeOffset(unixTime * TimeSpan.TicksPerSecond + unixEpochTicks, TimeSpan.Zero);
         }
     }
 }

Octokit/Helpers/UriExtensions.cs

@@ -4,8 +4,17 @@ using System.Linq;
 
 namespace Octokit
 {
+    /// <summary>
+    /// Extensions for working with Uris
+    /// </summary>
     public static class UriExtensions
     {
+        /// <summary>
+        /// Merge a dictionary of valeus with an existing <see cref="Uri"/>
+        /// </summary>
+        /// <param name="uri">Original request Uri</param>
+        /// <param name="parameters">Collection of key-value pairs</param>
+        /// <returns>Updated request Uri</returns>
         public static Uri ApplyParameters(this Uri uri, IDictionary<string, string> parameters)
         {
             Ensure.ArgumentNotNull(uri, "uri");

Octokit/Models/Response/AdditionsAndDeletions.cs

@@ -6,9 +6,17 @@ using Octokit.Helpers;
 
 namespace Octokit
 {
+    /// <summary>
+    /// Represents lines added and deleted at a given point in time
+    /// </summary>
     [DebuggerDisplay("{DebuggerDisplay,nq}")]
     public class AdditionsAndDeletions
     {
+        /// <summary>
+        /// Construct an instance of AdditionsAndDeletions
+        /// </summary>
+        /// <param name="additionsAndDeletions"></param>
+        /// <exception cref="ArgumentException">If the list of data points is not 3 elements</exception>
         public AdditionsAndDeletions(IList<long> additionsAndDeletions)
         {
             Ensure.ArgumentNotNull(additionsAndDeletions, "additionsAndDeletions");
@@ -21,10 +29,19 @@ namespace Octokit
             Deletions = Convert.ToInt32(additionsAndDeletions[2]);
         }
 
+        /// <summary>
+        /// Date of the recorded activity
+        /// </summary>
         public DateTimeOffset Timestamp { get; private set; }
 
+        /// <summary>
+        /// Lines added for the given day
+        /// </summary>
         public int Additions { get; private set; }
 
+        /// <summary>
+        /// Lines deleted for the given day
+        /// </summary>
         public int Deletions { get; private set; }
 
         internal string DebuggerDisplay

Octokit/Models/Response/CodeFrequency.cs

@@ -6,9 +6,16 @@ using System.Linq;
 
 namespace Octokit
 {
+    /// <summary>
+    /// Represents the summary of lines added and deleted
+    /// </summary>
     [DebuggerDisplay("{DebuggerDisplay,nq}")]
     public class CodeFrequency
     {
+        /// <summary>
+        /// Construct an instance of CodeFrequency
+        /// </summary>
+        /// <param name="rawFrequencies">Raw data </param>
         public CodeFrequency(IEnumerable<IList<long>> rawFrequencies)
         {
             Ensure.ArgumentNotNull(rawFrequencies, "rawFrequencies");