Remove SLF4j from uber-jar file, but keep it in dependencies

[klya]

SLF4j from logzio-appender clashes with the original library which has different version. This change fix it.

Here is example of this problem with logs: https://github.com/logzio/logzio-logback-appender/issues/20#issuecomment-357711853.

[yyyogev]

@klya thanks for your suggestion. We'll review it shortly

[yyyogev]

Looks good @klya , please remove the comment and we are good to go

[klya]

@yyyogev done!