add a simple introduction
init xcode project
Basic Bell Player functions
Fix bugs and finished the simple demo of osx
Merge pull request #2 from shanzi/master

Fix bugs and finished the simple demo of osx
完善 osx demo，添加音量和duration 控制
modified to support ios, finished iOS demo
Merge pull request #3 from shanzi/master

完善 osx demo，添加音量和duration 控制，兼容 iOS ，添加iOS Demo
create delegate for bellplayer
Merge pull request #4 from shanzi/master

create delegate for bellplayer
Merge branch 'master' of https://github.com/xiuxiude/bell

Conflicts:
	README.md