Re-add tag and suffix check

Author: zaccharles

build.cake

@@ -4,13 +4,21 @@ var configuration =
     HasArgument("Configuration") ? Argument<string>("Configuration") :
     EnvironmentVariable("Configuration") != null ? EnvironmentVariable("Configuration") : "Release";
 
+var preReleaseSuffix =
+    HasArgument("PreReleaseSuffix") ? Argument<string>("PreReleaseSuffix") :
+    (AppVeyor.IsRunningOnAppVeyor && AppVeyor.Environment.Repository.Tag.IsTag) ? null :
+    EnvironmentVariable("PreReleaseSuffix") != null ? EnvironmentVariable("PreReleaseSuffix") :
+    "beta";
+    
 var buildNumber =
     HasArgument("BuildNumber") ? Argument<int>("BuildNumber") :
     AppVeyor.IsRunningOnAppVeyor ? AppVeyor.Environment.Build.Number :
     TravisCI.IsRunningOnTravisCI ? TravisCI.Environment.Build.BuildNumber :
-    EnvironmentVariable("BuildNumber") != null ? int.Parse(EnvironmentVariable("BuildNumber")) : 0;
+    EnvironmentVariable("BuildNumber") != null ? int.Parse(EnvironmentVariable("BuildNumber")) :
+    0;
+
+var versionSuffix = string.IsNullOrEmpty(preReleaseSuffix) ? null : preReleaseSuffix + "-" + buildNumber.ToString("D4");
 
-var versionSuffix = "b" + buildNumber.ToString("D5");
 var artifactsDir = Directory("./artifacts");
 
 Task("Clean")