Fix broken download links for SQL Server

ref. http://tickets.opscode.com/browse/COOK-3507

The server SQL Express download links are broken, they return an HTTP "302 Moved Temporarily" response.
The broken links are:
http://care.dlservice.microsoft.com/dl/download/5/1/A/51A153F6-6B08-4F94-A7B2-BA1AD482BC75/SQLEXPR_x64_ENU.exe
http://care.dlservice.microsoft.com/dl/download/5/1/A/51A153F6-6B08-4F94-A7B2-BA1AD482BC75/SQLEXPR32_x86_ENU.exe