new branch modified:   battleship.py
fix 51 stirng for py3
new readme
create new grid
renew readme
draw boards
add/create background
add define for draw ships
	modified:   drawboard.py
	renamed:    more.png -> sea.png
	new file:   .gitignore
	modified:   drawboard.py
	new file:   ships.py
	deleted:    ships.pyc
	modified:   drawboard.py
	modified:   ships.py
	modified:   drawboard.py
	modified:   ships.py
	modified:   drawboard.py
	modified:   drawboard.py
	modified:   drawboard.py
	new file:   todo
	modified:   drawboard.py
	modified:   ships.py
	deleted:    todo
	modified:   drawboard.py
	modified:   ships.py
	new file:   todo
	modified:   drawboard.py
func cal space around ship