Split out helpers:
is_present() - check if the given path exists
is_dir() - check if the given path exists and it is a directory
make_parent_dir() - create the parent directories of the given path
These helpers will be reused in later commits.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Christian Lamparter <chunkeey@gmail.com>