Raise Git minimum, recommended version

Author: gerhardol

.github/PULL_REQUEST_TEMPLATE.md

@@ -18,5 +18,5 @@ What did I do to test the code and ensure quality:
 - 
 
 Has been tested on (remove any that don't apply):
-- GIT 2.10 and above
+- GIT 2.11 and above
 - Windows 7 and above

GitCommands/Git/GitVersion.cs

@@ -17,10 +17,10 @@ public class GitVersion : IComparable<GitVersion>
         private static readonly GitVersion v2_9_0 = new GitVersion("2.9.0");
         private static readonly GitVersion v2_11_0 = new GitVersion("2.11.0");
         private static readonly GitVersion v2_15_2 = new GitVersion("2.15.2");
-        private static readonly GitVersion v2_16_3 = new GitVersion("2.16.3");
+        private static readonly GitVersion v2_18_0 = new GitVersion("2.18.0");
 
-        public static readonly GitVersion LastSupportedVersion = v2_9_0;
-        public static readonly GitVersion LastRecommendedVersion = v2_16_3;
+        public static readonly GitVersion LastSupportedVersion = v2_11_0;
+        public static readonly GitVersion LastRecommendedVersion = v2_18_0;
 
         private const string Prefix = "git version";