Feature Request: Logging

Hi,

We have just started to use wyUpdate & wyBuild for our update process and noticed that there seems to be no logging support on update process. For example, it would be great if you log the offending file name when you throw the following exception:

throw new PatchApplicationException("Patch failed to apply to this file: " + FixUpdateDetailsPaths(file.RelativePath) + "\r\n\r\nBecause that file failed to patch, and there's no \"catch-all\" update to download, the update failed to apply. The failure to patch usually happens because the file was modified from the original version. Reinstall the original version of this app.\r\n\r\n\r\nInternal error: " + IOEx.Message);

This would greatly help during debugging to see which file is modified. Specifying a log path and verbosity level would be great to diagnose update issues.