add TimerManager
TimeManager is building to manage timer for update on the same time
this commit also let countdown aply this setting.
rename timer getStatus method to isTimeUp
also simplify countdown.lua source code
add "addTimeLife()" method on timer
add campfire
Merge branch 'master' into fntsrlike

Conflicts:
	classes.lua
	main.lua
	r.lua
comment something todo at campfire
Merge branch 'master' of https://github.com/raincole/isr

Conflicts:
	classes.lua
	main.lua