loaded dll instead when intent to load specification config

[Guanglei Li]

The convention which concordion uses to locate the specification configuration is "replacing the .dll extension with the .config extension". While Windows is case insensitive. On some machine (at least mine), the dll file contains spec is XXX.DLL, which the extension is uppercase. So the replacement failed since no lowercase "dll" found and the original dll file path was returned as the configuration file. Then when the parser tries to parse it as xml, it failed for sure.

The fix is quite simple, just as the following code:

- var configFileName = pathToAssembly.Replace(".dll", ".config");
+ var configFileName = pathToAssembly.ToLowerInvariant().Replace(".dll", ".config");