Build - core: main: remove all the spam about including make files

Change-Id: Icb98d2b768a2139a58eff303071d6bd0d77da44d
Signed-off-by: STELIX <ssspinni@gmail.com>
Build - envsetup: do not print an error if complete fails

complete is a bashism; so it will fail on other shells. Avoid printing
an error if that is the case.

Change-Id: If72fbca96e8b4f8b0c9022f4b2cacc86d7dd9eb0
Signed-off-by: STELIX <ssspinni@gmail.com>