"js2-mode is developed by an eccentric developer called Steve Yegge"
I think the translator didn't get it right when he/she called Steve Yegge "Eccentric." Google translate makes no mention of this, while Bing describes js2-mode as "unusual, which makes more sense:
"js2-mode new JavaScript for measure mode made by Developer Steve Yegge is somewhat unusual, as implemented in Emacs Lisp"