Reorganize visualization.
Correct typos.
Move utils function to a new utils chapters.
Merge branch '0.7'
Merge remote-tracking branch 'vidars/live-component-plot-update' into 0.7.1
BUG_FIX: Signal._assign_subclass was not changing the subclass when setting signal_origin due to a typo.
Automatic style corrections courtesy of autopep8.
Add test.
Automatic style corrections courtesy of autopep8.
Merge pull request #273 from francisco-dlp/BUG_FIX_assign_subclass

Bug fix assign subclass
Option for modal interactive dialogs

Added options for interactive GUI tools to be modal, allowing e.g. for
scripting general routines.
Added modal interactive range selector decorator

Added a decorater for a interactive range selector that is modal
(kind='livemodal').