Rename all files in a folder to upper case

Location: /opt/scripts/renameuppercase.sh (May 2016, 1 line of logic) 
 Purpose 
 Renames every file in the current folder to upper case (for example photo.jpg becomes PHOTO.JPG ). 
 How it runs 
 By hand, from inside the folder you want to change. 
 Usage 
 cd /path/to/folder && /opt/scripts/renameuppercase.sh
 
 Dependencies 
 tr , mv . 
 What it touches 
 Every file name in the current folder. There is no undo.