Feature: New Logging provider

[lukeblevins]

Closes #11918

• Switches logging to go through the centralized generic host
• Sets the default logging level to LoggingLevel.Information
• Creates a simple FileLoggingProvider since a default implementation isn't available yet
• Removes old platform-specific log writer
• Changes remaining parts of app to use new ILogger
• Entries with LogLevel.Warning or higher will also be written to the Windows Event Log
• Incorporate changes from Fix: Remove unnecessary log spam #11933 (by @hecksmosis)

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[yaira2]

LGTM

[yaira2]

@lukeblevins can you fix the merge conflict?