The loading bolt was being shown in several distinct places, which was
resulting in a glitch between completing onboarding and showing the
wallet ui.
Refactor such that the LoadingBolt component is only mounted once, in
the root component.
Rather than using relative paths for css imports - which can break when
we move files around - add our styles path to the webpack sass-loader
loader using the `includePaths` setting.
Tom Kirkpatrick
Jack Mallers