Update version strategy in appveyor.yml

Author: daviwil

appveyor.yml

@@ -1,4 +1,5 @@
-version: 0.2.0.{build}
+#TODO: Remove '-beta' for 1.0 release!  This is to identify as prerelease on NuGet
+version: 0.2.0-beta+{build}
 os: Unstable
 configuration: Release
 clone_depth: 10
@@ -18,7 +19,7 @@ branches:
 assembly_info:
   patch: true
   file: '**\AssemblyInfo.*'
-  assembly_version: '0.2.0'		# This version number should always have 0 for the last section
+  assembly_version: '{version}'
   assembly_file_version: '{version}'
   assembly_informational_version: '{version}'