Bug 852852:  Assgin GAIA_PATH as "$(LOCAL_PATH)/../gaia" when it's not defined. r=mwu
When $(GAIA_PATH) is not exist make error message about it.
Merge pull request #77 from ChangbinPark/master

Bug 852852:  Assgin GAIA_PATH as "$(LOCAL_PATH)/../gaia" when it's not defined. r=mwu