Removed trailing white spaces

Removed trailing whitespaces with

```sh
for file in `grep -r " $" * | cut -d : -f 1 | sort | uniq | grep -v " "`; do sed -i 's/[ \t]*$//' $file; done
```

and some handwork.

cmd/web.go

@@ -42,7 +42,7 @@ import (
 var CmdWeb = cli.Command{
 	Name:  "web",
 	Usage: "Start Gogs web server",
-	Description: `Gogs web server is the only thing you need to run, 
+	Description: `Gogs web server is the only thing you need to run,
 and it takes care of all the other things for you`,
 	Action: runWeb,
 	Flags:  []cli.Flag{},