Remove "RC" from image since Visual Studio 2017 is now officially released.

codecadwallader · codecadwallader · commit c1038df28ec2 · 2017-03-26T19:09:37.000Z
diff --git a/appveyor.yml b/appveyor.yml
@@ -1,5 +1,5 @@
 version: 10.3.{build}
-image: Visual Studio 2017 RC
+image: Visual Studio 2017
 
 install:
   - ps: (new-object Net.WebClient).DownloadString("https://raw.github.com/madskristensen/ExtensionScripts/master/AppVeyor/vsix.ps1") | iex
