Fixes log message when return_to match failures occur.

Fixes #249
Merge remote-tracking branch 'origin/v4.0' into v4.0
Restore constructor which breaks OauthWebSecurity

This is to fix issue 251 on Github:
https://github.com/DotNetOpenAuth/DotNetOpenAuth/issues/251

This will re-break the following issue, which needs more thought to
correctly implement.

http://stackoverflow.com/questions/12235395/openauth-requestauthentication-throws-null-ref-in-vs2012-web-forms-template/12240150#12240150
Fix spacing
Merge branch 'v4.2' of git://github.com/nikolawannabe/DotNetOpenAuth into nikolawannabe-v4.2
Fixes whitespace build breaks in release
Fixes runtime failure with ASP.NET authentication module.

Closes #267
Closes #251.
Applies fix for #209 to one more entrypoint for parsing XML that was missed initially.
Merge branch 'v4.0' into v4.1
Merge branch 'v4.1' into v4.2
Merge branch 'v4.2' into v4.3