Ability to save and share settings

[simonswain]

When you change settings, app should use pushState to set the url to a query string that contains the settings, so they can be easily shared. Off the back of this, provide a list of presets (in a dropdown) for different scenarios. Need a Title field for the settings too.

[simonswain]

Have enabled basic sharing - settings now get placed in URI as query params when they are changed. Using the query will cause the sim to be started with those options.