Use scratch-storage

Attaching the storage module in `vmListenerHOC` means it can propagate
down to the GUI, stage, and blocks naturally. The default VM property
value has been removed from those places so that we're not instantiating
extra VM instances any more. Instead, using one of those components
outside of the `vmListenerHOC` framework will require providing a VM
instance as a property.

Tabbed sound and costume panels

Sound library first iteration

Remove target pane button and actions

Add back putting the sound library in the ui

Fix block editor borders 

There are a handful of places where the GUI code could use the storage
module directly; converting those is for a later change.

Fixes #156 + refactored classnames to style guide conventions

Affects SpriteSelector Pane, StageSelector Pane, Stage, MenuBar, Libraries Modal, Add/Import buttons, for Chrome, Ffx + Safari on Sierra.

Fixes #162

Add simple blocks background pattern

* Update blocks.js

Store the scroll/zoom of the workspace on a per-target basis

Fixes #220

* chore(package): update react-redux to version 5.0.3

https://greenkeeper.io/

* chore(package): update style-loader to version 0.13.2

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* chore(package): update react-modal to version 1.7.2

Closes #151

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* chore(package): update postcss-loader to version 1.3.3

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* chore(package): update babel-loader to version 6.4.0

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* chore(package): update css-loader to version 0.26.4

Closes #133

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* Trust babel for the future

Sprite delete button

* Buffer sprite info text fields

Changes to the name, x, or y fields should only be sent to the VM when the field is blurred or when enter is pressed.

Still allow updates while the fields are focused, but unchanged.

Fixes #154

* Remove focus from input fields after hitting enter

* Fix prop types for info component and container

Refactored towards better convention for linting.

Add sounds to each letter sprite in the library