updated app.config file to add Npgsql as a data provider for this app.

DbProviderFactories.xml

<!--Ref: http://outofmemory.azurewebsites.net/configure-npgsql-on-windows/ -->
<?xml version="1.0" encoding="UTF-8" ?>
<configuration>
 <connectionStrings>
   <add name="hockeydb" 
   		connectionString="Server=127.0.0.1;Port=5432;Database=hockeydb;User Id=demo;Password=demo;" 
   		providerName="Npgsql" 
   		/>
  </connectionStrings>
        
<system.data>
   <DbProviderFactories>
	<add name="PostgreSQL Data Provider"    invariant="Npgsql"    
		 description=".Net Framework Data Provider for PostgreSQL" 
		 type="Npgsql.NpgsqlFactory, Npgsql, Version=4.0.0.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7"/>	   
   </DbProviderFactories>
	
   <DbProviderFactories>
	    <add name="Npgsql Data Provider" invariant="Npgsql"
		 description="Data Provider for PostgreSQL"
		 type="Npgsql.NpgsqlFactory, Npgsql" /> <!-- explicit-->
  </DbProviderFactories>
 </system.data>
 
 </configuration>