rename gora to cmd. gofmt
review change

1, use flag.PrintDefaults in Usage, instead of custom print. os.Exit(0) -> os.Exit(1)
2, gorazor.GenFile should check error. os.Exit(2) on error
3, change util.go Caplitalize
4, can't compile dir, go_extension->gz_extension
5, regex.FindIndex -> regex.FindStringIndex, for performence. reduce memory copy
6, file mode 0777 -> 0644?
mkdir with 0775