From the current location inside "cmd" the npmExecutorMock cannot
be used from any coding inside "pkg".
When we would like to re-use the npm functionality we have also to
provide tests and this requires having a mock.
In order to be able to use the mock from pkg we move the mock from
"cmd" to "pkg" into package "npm".
With the shift from package "cmd" to "npm" a lot of fields in the mock
has been made public.