enables all optional nodes when running dev server

[iturgeon]

Dev/18 added last minute code to disable optional nodes by default. This turns them on when running the dev server yarn dev

Materia is the only optional node right now, so you should be able to test by running dev/19 and running this branch

With this change you'll see obojobo-chunks-materia/server/index.js get loaded and you'll see the Materia button in the editor

OboNode client scripts to build 7
  obojobo_server:info  Registering express middleware: /Obojobo/packages/obonode/obojobo-chunks-materia/server/index.js +0ms
  obojobo_server:info  Registering express middleware: /Obojobo/packages/app/obojobo-module-selector/server/index.js +5ms
  obojobo_server:info  Registering express middleware: /Obojobo/packages/app/obojobo-repository/server/index.js +1ms
  obojobo_server:info  Registering express middleware: /Obojobo/packages/obonode/obojobo-sections-assessment/server/express.js +21ms
  obojobo_server:info  Registering OboNode: ObojoboDraft.Chunks.MCAssessment +6ms
  obojobo_server:info  Registering OboNode: ObojoboDraft.Chunks.MCAssessment.MCChoice +0ms
  obojobo_server:info  Registering OboNode: ObojoboDraft.Chunks.QuestionBank +1ms
  obojobo_server:info  Registering OboNode: ObojoboDraft.Chunks.Question +1ms
  obojobo_server:info  Registering OboNode: ObojoboDraft.Sections.Assessment +0ms