Custom procedures reducer, modal and block workspace.

src/components/custom-procedures/custom-procedures.css

src/components/custom-procedures/custom-procedures.jsx

src/components/custom-procedures/icon--boolean-input.svg

src/components/custom-procedures/icon--label.svg

src/components/custom-procedures/icon--text-input.svg

src/containers/blocks.jsx

src/containers/custom-procedures.jsx

src/reducers/custom-procedures.js

src/reducers/gui.js

test/integration/test.js