run npm update and include node_modules #16079

Fixes #16030

Also includes the node_modules folder as discussed on slack to keep matomo working for users who do not have servers with node and deploy from git.

@diosmosis guess if we include the node_modules in core, we might need to remove the automatic npm update in travis builds again? so we can be sure all files that are needed are actually commited

Yes that be good 👍

@sgiehl / @tsteur changes should be made.

👍 looks all good from my perspective... be good if @sgiehl confirms too

Looks good to me too. Guess we need to merge the change to travis-scripts to master and update the submodule here before merging...