Wonder 8 removes log4j

[Ramsey Gurley]

Hi all,

I've just pushed a commit removing all log4j dependency in Wonder 8, and 
migrated it to SLF4J2. A few useful things had to die in 
er.extensions.logging, but if they are useful enough, someone will 
re-implement them. I personally really liked the log4j configuration 
page and will probably add that back in the future with log4j2 in a 
separate framework. In any case, logging is now entirely up to the end 
user. You can use logback. You can use JUL. You can use log4j2. Whatever 
you like, via the SLF4J api. Log4J2 looks pretty nice with non-blocking 
log io, but you're welcome to use what you like.

Ramsey