include path and virtual procject directory fixed

these patch fix https://github.com/diabolo38/STM322F4-disco/issues/1

all include forlder now part of the proejct as virtual and linked folder 
it avoid teh previous mess-up with path and build variable. 
That way eclipse resolve all path in a better ways.
also the include are indexed and can be browse nagivate to in source
editor more easily