Implements basic skipped items logic

And adds/updates some documentation
Implements basic error catching based on url names

In admin, when refresh or back button is used.
Adds module references to skipped items
Implements misc optimizations

Removes the necessity to have pages with selectors in a certain order
in each JSON
Optimizes uninstallation output
Fixes notices
Adds some test JSON files
Adds breadcrumb to export page
Merge branch 'install-output-optimization' of https://github.com/owzim/ProcessJSONInstaller into owzim-install-output-optimization

Conflicts:
	ProcessJSONInstaller.module
Merge branch 'owzim-install-output-optimization'