Pin Cake versions to a set that works together.

Author: rstam

build.cake

@@ -1,7 +1,7 @@
-#addin "nuget:?package=Cake.FileHelpers"
-#addin "nuget:?package=Cake.Git"
-#addin "nuget:?package=Cake.Incubator"
-#tool "nuget:?package=GitVersion.CommandLine"
+#addin "nuget:?package=Cake.FileHelpers&version=3.1.0"
+#addin "nuget:?package=Cake.Git&version=0.19.0"
+#addin "nuget:?package=Cake.Incubator&version=3.1.0"
+#tool "nuget:?package=GitVersion.CommandLine&version=4.0.0"
 #tool "nuget:?package=xunit.runner.console"
 
 using System.Text.RegularExpressions;