Contextually.NET45 AppDomain bug resolution

Resolves a bug where InfoBlock didn't serialize across AppDomains causing an unhandled exception.

Documentation: XML Comment file

Simply adds XML files to the nuget package.

Bugfix: Thread-safety for named containers

Fixed a non-thread-safe dictionary for named containers.

Added Relevant Info Containers

Adds features requested in feature request #1 and merged in with PR #2.