update demo
Merge branch 'gh-pages' of github.com:coolwanglu/PDCurses-emscripten into gh-pages

Conflicts:
	web/firework.js
	web/newdemo.js
	web/ptest.js
	web/rain.js
	web/sdltest.js
	web/testcurs.js
	web/tuidemo.js
	web/worm.js
	web/xmas.bc
	web/xmas.js