Update to 0.15.0 PureScript

[JordanMartinez]

Description of the change

Fixes #273. Still a WIP. Besides updating the server code, I also updated the client and staging code to 0.15.0.

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Checklist:

• Added the change to the changelog's "Unreleased" section with a reference to this PR (e.g. "- Made a change (#0 by @)")
• Linked any existing issues or proposals that this pull request should close
• Updated or added relevant documentation
• Added a test for the contribution (if applicable)

[JordanMartinez]

This should be removed once debug gets added to the package set.

[JordanMartinez]

Perhaps we should use 3 spago.dhall files: a shared one, one for dev and one for prod?

[mikesol]

This looks really good! I tried to hack at it a bit and spotted that setupIFrame and teardownIFrame are exported from Container.js without being defined there, which may be problematic for esbuild. Is that the bundler you're going to use for the client?

[mikesol]

@JordanMartinez if you want to assign me as a reviewer I can mark the places where I needed to make changes for my dockerized version of trypurescript (the one on try.wags.fm). Some of them will be needed for this PR as well (for example, I hit the esbuild issues with top being a reserved word, etc).

[JordanMartinez]

@mikesol This PR will need to update the code to do both #263 and #264.

setupIFrame and teardownIFrame are exported from Container.js without being defined there, which may be problematic for esbuild

Looks like those two functions are defined in client/public/index.html. Since we'll be using SystemJS, I don't think we'll implement the code in the same way as before, so this might be a moot point.

[JordanMartinez]

Succeeded by #275