Fixed incorrect formating of cacheDuration in metadata.
- The cacheDuration should be formatted as an XML duration.
- Fixes #115.
- Changed the cacheDuration to use a TimeSpan internally and in config.
Updated doc with metadata cache duration format.
Fix for #115 Invalid format of cacheDuration in metadata.
Added link to the SAML specs to contribution guidelines.
Cleaned up readme files.
- The readme files contained config examples which were terrible outdated. Removed those, too much work to maintain them.