This commit removes the env_logger dependency, replacing it with a simple implementation. Doing so removes like ten other transitive dependencies that no longer need to be included in the build.
It also gains the ability to enable trace-level logging. The users crate, which contains such logging statements as of the version I published a few days ago, has been upgraded to celebrate.
Also, change the log imports to globs. I'm only interested that a file doing logging, not what level it's logging at.
Again, it was hard to read and edit this text when it was in a string inside an echo command inside a bash script inside a heredoc inside a Ruby script wrapped in a mystery. It also gives me space to write some actual comments.
