We've been hard-coding paths to node.js-based executable files, pointing

to some place in node_modules/<module>/.... We've seen this change a

couple of times now, particularly with Babel.
There's already a built-in solution to this that makes our lives easier,

reduces maintenance, and better survives module updates. Each executable

has a symlink in node_modules/.bin/, which references the correct path

within the module.
This change updates our static media building to reference these more

stable paths.

Successfully built packages, and verified through ps auxw that the

.bin/ paths were being used.