AsyncIO version of xAAL Lib. This code use the core
 lib and provide additionnal async functionnalities. 

A lot of work to be done:
- device handlers doesn't support coroutine right now
- timers should be reworked.

In future, this lib can be merged w/ the core one, or 
replace it. not really clear now.




git-svn-id: https://redmine.imt-atlantique.fr/svn/xaal/code/Python/branches/0.7@2714 b32b6428-25c9-4566-ad07-03861ab6144f