Remove node_modules in prep for Dockerization

Having node_modules in the tree is not going to work well with docker. Virtualbox shared folders doesn't support symlinks so running a rebuild on hosted src will not work.

Whilst we thought there were benefits with this in the past I'm quickly becoming not convinced it's a good way to go.

With a standard set of npm deps we can install via the image build, which can be in the dir above the src tree (this works because node will walk up the tree until if finds a node_modules dir). The only other thing is we have to workaround the way grunt loadTasks works which is added to the Gruntfile in this PR.

This way dockerization helps with the repeatability and we don't need a massive pile of node_deps in the tree.

r? @kumar303