Merge branch 'patch-1' of https://github.com/micsco/Cake.BuildSystems.Module into micsco-patch-1

Author: agc93

src/Cake.TeamCity.Module/TeamCityLog.cs

@@ -16,7 +16,7 @@ public TeamCityLog(IConsole console, Verbosity verbosity = Verbosity.Normal)
 
         public void Write(Verbosity verbosity, LogLevel level, string format, params object[] args)
         {
-            if (!string.IsNullOrWhiteSpace(System.Environment.GetEnvironmentVariable("TF_BUILD")))
+            if (!string.IsNullOrWhiteSpace(System.Environment.GetEnvironmentVariable("TEAMCITY_VERSION")))
             {
                 switch (level)
                 {
@@ -56,4 +56,4 @@ private string Escape(string text)
                 .Replace("]", "|]");
         }
     }
-}
+}