added gitignore with all the module

Signed-off-by: Luca Clementi <luca.clementi@gmail.com>
Added script to download all the submodule

Signed-off-by: Luca Clementi <luca.clementi@gmail.com>
Track execution time

Signed-off-by: Luca Clementi <luca.clementi@gmail.com>
More docuementation on the import process

Signed-off-by: Luca Clementi <luca.clementi@gmail.com>