Allow pointer events to fall through the overlay

Add reducer, components and containers for monitors

Minor-pin all Scratch 3.0 prerelease modules

Toggle turbo mode when shift clicking the green flag

Pin these modules to 0.*-prerelease.* to avoid problems when we
eventually bump to 1.x

Add prompt for variable creation

Stringify project data

Otherwise the VM can't JSON.load it.

Stop clobbering loading projects with default data

Fix whitespace canvas

Replace draggable with direction input

Get `Asset` and `AssetType` from storage instance

Update babel-loader to the latest version 

This version of babel-loader dropped support for Node < 4. Although 4.2 >= 4, update to 6  for consistency with our other repos, and so that we stay ahead of the curve for any other packages.

If the app is loading with an initial project id, don't try to load the default project. Previously, this data would load on top of the project being loaded.

Does not fix the issue of blocks not loading in the blocks pane, which appears to be separate.