Fixing issue with arguments 

Argument passing seems not working, at least with llvm 3.2
Argument variable in function is a random value (readed from not initialized RAM, probably)
I have only tested with llvm 3.2, so I don't know if the change is backward compatible.

* First commit:
  * **example.txt**: Modified, show the issue

* Second commit:
  * **codegen.cpp**: Modified, adding a Store instruction for each argument passing during method declaration impl