Merge branch 'develop' of https://github.com/octobercms/october into feature/PSR-2

Conflicts:
	modules/backend/behaviors/UserPreferencesModel.php
	modules/cms/classes/Controller.php
	modules/system/classes/CombineAssets.php
Be more specific about pathing, minor improvement to system settings table
Merge branch 'develop' of https://github.com/octobercms/october into feature/PSR-2

Conflicts:
	modules/backend/behaviors/RelationController.php
	modules/backend/classes/WidgetManager.php
	modules/cms/classes/CmsCompoundObject.php
	modules/cms/twig/Extension.php
	modules/cms/twig/PlaceholderNode.php
	modules/cms/widgets/TemplateList.php
Updating modules/system
Peer review of #679
Fixes omitted visibility
Fixes an issue where new Themes attached to a project were not being installed on update.
Update Font Autumn icon pack
Update icons
Revert to FA-only icons