Convert logging solution to Serilog

[dkbennett]

Summary of the pull request

Converts all logging infrastructure in Dev Home over to using Serilog. This conversion is a 1:1 translation for the most part, removing the old in-house logging solution and replacing it with Serilog. Further optimizations and improvements can be made now that the logging is moved to a more consistent paradigm with Serilog. This also works much better with Dependency Injection, which is one of the foreseen next steps following this conversion.

References and relevant issues

Detailed description of the pull request / Additional comments

• Entirely removed old logging solution and all of its references.
• Added Serilog and Serilog ILogger into the services.
• Converted previous static logging over to Serilog static logging.
• Updated log locations and format.
• Added appsettings.json for DevHome for the HyperV extension and the Core Widgets extension.
• Updated appsettings for DevHome with Serilog configuration data.
• Log files are more consolidated now, with DevHome having a single log, the Core Widgets extension having a single separate log, and the HyperV extension having a single separate log. All log files are now under the temp folder under "Logs" with a sub folder for each of these three main programs.
• Did not adjust the verbosity of logs, leaving filtering to tooling and verbosity adjustments to be made in a subsequent PR. This is relevant since the logs are now combined instead of separate. Chattier components may make the logs a little more difficult to read but can be alleviated by log parsing tooling.

Validation steps performed

• Built all of the solutions, debug and release in VS and using build scripts.
• Cloned repository by URI
• Added and configured widgets, core widgets, and hyper v.
• Verified log file locations were correct and output was in the expected format.

PR checklist

• Closes #xxx
• Tests added/passed
• Documentation updated

[dkbennett]

/azp run

[azure-pipelines]

Pull request contains merge conflicts.

[dhoehna]

Looks good in my area.