v0.13.5

• Update to v0.13.5 of the compiler (@natefaubion)
• Remove backends, serve individual modules on demand (@natefaubion, @gabejohnson, #128, #136)
• Host the client ourselves rather than using GH pages
• Put all source files in one branch (@gabejohnson, #135)
• Fix gist navigation within the iframe (@natefaubion, #140)
• Use different sourceURL syntax per warnings (@natefaubion, #141)
• Switch to spago for managing PS dependencies (@hdgarrood, #147, #150)
• Build the frontend in CI (@hdgarrood, #152)
• Mostly automated deployments (@hdgarrood)