Fix appveyor csproj version patching.

Author: msallin

SQLite.CodeFirst/SQLite.CodeFirst.csproj

@@ -4,6 +4,7 @@
     <TargetFrameworks>net40;net45</TargetFrameworks>
     <Authors>Marc Sallin</Authors>
     <Company />
+    <Version />  <!-- This empty tag is necessary to make appveyor csproj version patching work! -->
     <Description>Creates a SQLite Database from Code, using Entity Framework CodeFirst.  This Project ships several IDbInitializer which creates a new SQLite Database, based on your model/code.</Description>
     <PackageProjectUrl>https://github.com/msallin/SQLiteCodeFirst</PackageProjectUrl>
     <RepositoryUrl>https://github.com/msallin/SQLiteCodeFirst</RepositoryUrl>