macro: Rename 'jsduck' to 'jsduck-conf' and create new 'jsduck'

This is the first step towards standardising on 'jsduck.json'
(which is now supported by JSDuck 5 as the standard filename
when not overriding it).

This joins the pool of standard file names we have already,
such as: .gitignore, .jshintrc, Gruntfile, and package.json.

Change-Id: Iaa09a266fbc315401502b780465a830176775c31