Repository Commits Get All

Added the logic for getting all commits for a repository including unit
tests and XML docs

Octokit/Clients/RepositoryCommitsClient.cs

@@ -1,4 +1,5 @@
-using System.Threading.Tasks;
+using System.Collections.Generic;
+using System.Threading.Tasks;
 
 namespace Octokit
 {
@@ -28,5 +29,19 @@ namespace Octokit
 
             return _apiConnection.Get<CompareResult>(ApiUrls.RepoCompare(owner, name, @base, head));
         }
+
+        /// <summary>
+        /// Gets all commits for a given repository
+        /// </summary>
+        /// <param name="owner">The owner of the repository</param>
+        /// <param name="name">The name of the repository</param>
+        /// <returns></returns>
+        public Task<IReadOnlyList<GitHubCommit>> GetAll(string owner, string name)
+        {
+            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
+            Ensure.ArgumentNotNullOrEmptyString(name, "name");
+
+            return _apiConnection.GetAll<GitHubCommit>(ApiUrls.RepositoryCommits(owner, name));
+        }
     }
 }