Correct fix for property get set definition generation.
Reverting the change in as3hx_config.xml & fixing Writer.hx.

Why reverting as3hx_config.xml?
changing 'get_%i' to 'get' results in below regression:
 - all method names are hard coded to get and set.
 - we still want method names to be get_%i and set_%i
 - only property declaration should have just get, set.