Setup custom 404 page

[htynkn]

There is a 404 page[1], but when we access wrong url, it will show apache default 404 page[2].

Something is wrong in here. we need fix configuration and also make small changes to existing page (it has different color)

[1] http://dubbo.apache.org/404.html [2] http://dubbo.apache.org/404_NOT_FOUND

[htynkn]

Reopen this since 404 page are not generated by hugo (still using old page)