recipetool: create: shrinkwrap and lockdown npm modules
"npm shrinkwrap" creates a file that ensures that the exact same
versions get fetched the next time the recipe is built. lockdown is
similar but also includes sha1sums of the modules thus validating they
haven't changed between builds. These ensure that the build is
reproducible.
Fixes [YOCTO #9225].
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
