Remove devsetup and clean up bundling

[rdeits]

Replaces #102, fixes #101

I was able to get rid of the devsetup() step entirely, and get rid of its associated node_modules folder in deps. Since we were already doing a npm install in the bundlejs() step, I don't think there's much reason for a separate devsetup().

I've tightened the version restrictions in package.json and checked in package-lock.json so we'll have a clear idea when package versions change. Unfortunately, this doesn't guarantee future compatibility, because npm install overwrites, rather than respecting, package-lock.json. It looks like making that guarantee will be possible with npm 5.7.1 using the npm ci command: npm/npm#18286 (comment)

By the way, bundlejs(watch=true) still works after this change 🙂

Also, we should check if this helps with #79 and #94

[codecov-io]

Codecov Report

Merging #103 into master will increase coverage by 0.15%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master     #103      +/-   ##
==========================================
+ Coverage    60.8%   60.95%   +0.15%     
==========================================
  Files          14       14              
  Lines         398      397       -1     
==========================================
  Hits          242      242              
+ Misses        156      155       -1

Impacted Files	Coverage Δ
src/devsetup.jl	0% <0%> (ø)	⬆️

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[shashi]

I'm not sure now if this still supersedes #99. Let me know and I'll merge the right PR.

Thanks!

[rdeits]

Yeah, sorry, I tried to keep the changes here separate from #99 but it all got kind of mixed together in the end. I'll close this so we can focus on a single set of changes.