Housekeeping: review use of ILogger instead of LogManager

[dpvreony]

Need to review use of ILogger instead of LogManager

• ReactiveUI: potential that some of the unit tests are watching a non-functioning logger
• Website: doc's need looking at
• Splat: Remove ILogger init, or have a default that returns the default logger from LogManager.

https://github.com/search?p=1&q=org%3Areactiveui+ilogger&type=Code