Cleaner markup with less inline styling and miscellaneous bug fixes/optimisations

• Moved child state and recalculation of child spaces to the parent space to remove synchronisation issues causing various update issues.
• Moved space styles to document head to generate cleaner mark-up. All spaces now get a auto-generated short ID which can be overriden with the id property on a space.
• Removed the need for an outer and inner container on all spaces except for when a space is resizable and scrollable to allow the space to maintain the resize handle location.
• Optimised touch resize actions preventing default browser actions using css touch-action and changing debounce to throttling on resize updates.