LPS-45853 Single page application utility
LPS-45853 Disable single page application for ajaxy portlets to avoid navigation conflicts

- Asset Category Admin
- Asset Tag Admin
- Nested Portlet
LPS-45853 Standardize portlets markup incosistencies to fit surfaces contract
LPS-45853 Do not force post action urls when single page application is enabled
LPS-45853 Liferay.History should not fire change for foreign states
LPS-45853 Fix and simplify logic for portlet events to handle dynamic portlet addition and removals
LPS-45853 Include system portlets to Liferay.Portlet.list
LPS-45853 Add themeDisplay.getLayoutRelativeURL method
LPS-45853 Do some clean up on single page application navigation