Convert all logging to Serilog

[dkbennett]

Summary of the pull request

Log conversion from serilog, very similar changes as: microsoft/DevHomeAzureExtension#143

References and relevant issues

Detailed description of the pull request / Additional comments

• DevHome.Logging removed.
• Serilog and related nuget packages added.
• appsettings.json added to the project with log settings.
• All static logging converted over to Serilog
• Some log levels were changed for spammier components.
• New logging added in places using lazy initialization.
• TestContext sink added in place of TestListener, which writes Serilog events to the TestContext.
• Updated all test setups to automatically log and output log messages to TestContext. This means any logs generated during test runs by components will be captured in both a temporary log and in the test output for easy analysis.
• Updated testconsole with logging setup so ad hoc testing with it is already configured for logging.

Log formatting changes:

• Log format was changed to be more compact, easier to parse and be human-readable.
• Log format is similar to Serilog's default modified to be close to the previous log format.
• Single log instead of multiple logs.
  Log has a daily interval where it will be a new file, rolling over 30 days.

Validation steps performed

• Ran all tests and ensured they are producing logs and TestContext messages as well as passing.
• Scenario tested widgets and verified logging.
• Cloned a github repository by url

PR checklist

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

[krschau]

Should this not be included, or should we include canary as well?

[dkbennett]

We should include all of the devhome and extension package name variants so the logging of packages present is complete.

[krschau]

Not sure if you wanted to include the other flavor/extensions from my other comment, but can be done after.