[Feature suggestion] Log option on admin area

Hi guys,

Sometimes I want to see Gogs logs to see if anything is wrong, but today I need to go to gogs `log` folder to see logs.

Then I think that is good idea to add a Logs options on Gogs admin area and display `gogs.log`, `http.log`, `serv.log`, `update.log` and other Gogs logs. With this will be possible to see logs on Gogs install more easy and to report issues too.

What you think guys?
