Make it easier for the user to set the log level.
Make it easier for the user to set the log level.

Add two convenience functions that convert some reasonable form of user
input, especially the kind of values that could be read from the command
line, into a log level.

KenKundert/nonstdlib,kalekundert/nonstdlib,kalekundert/nonstdlib,KenKundert/nonstdlib