Logging

This project employs the logging utility facade SLF4J, using Apache Log4j ,
accordingly 2.x as its backend. Accordingly, levels of detail can be specified as follows:```

OFF:	The highest possible rank and is intended to turn off logging.

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ERROR:	Designates error events that might still allow the application to continue running.

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WARN:	Designates potentially harmful situations.

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INFO:	Designates informational messages that highlight the progress of the application at coarse-grained level.

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DEBUG:	Designates fine-grained informational events that are most useful to debug an application.

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TRACE:	Designates finer-grained informational events than the DEBUG.

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ALL:	All levels including custom levels.

For more guidance on which level to use, see Coding Conventions#Logging

For modifying
```One mechanism of globally effecting the log output of a running client is though modification the file
`/besu/src/main/resources/log4j2.xml`, where it can be specified under the `<Property name="root.log.level">`.
As such, corresponding instances of information logs throughout the codebase, e.g. `log.fatal("Fatal Message!");`,
will be rendered to the console while the client is in use, you may use a custom log4j config file by setting a system property at startup.  Besu's logging doc provides good documentation on how to configure logging in Besu.