Make the constructors of ILogProvider implementations more gump.
Update nuget packages.
- Rock.Core to 0.0.2
Overhaul of file configuration and logger factory.
 - Lots and lots and lots of changes.
Some minor changes.
Rename XmlDeserializingFactory; xml documentation.
XmlDeserializingFactory<T> -> XmlDeserializationProxy<TTarget>
Rename inheritors of XmlDeserializationProxy<TTarget>.
*Factory -> *Proxy
Change namespace of XmlDeserializationProxy; add documentation.
Remove unnecessary method override.
Rename private field.
_formatterFactories -> _formatter
Update Rock.Core nuget package; remove XmlDerializationProxy class.
The XmlDerializationProxy class is now included in Rock.Core.
Move Category class to /Configuration/Xml folder.
Add Default.Restore* methods.
Default.LoggerFactory has a better default value.
 - Add SimpleLoggerFactory class.
 - XmlDeserializingLoggerFactory uses a default category if missing.
Move SimpleLoggerFactory.
Remove Default.ContextProviders.
Remove unnecessary singleton pattern.
Remove unused types.
If the file's directory doesn't exist, create it.
Remove unnecessary constructor.
Add documentation. Mostly.