new class name for NumberTextBox
setting select value initially when thee is only one option
added editor editor
only copy common attributes on type switch if the attribute is exactly equal
force validation by setting wasBlurred in validatabe widgets
fire value-changed when adding removing from list
set value to first option if value is required and empty
replaced valid by state
fixed ref resolution. editor now works with circular referenes.
added schemas to factories
Merge branch 'feature/circular_references'

Conflicts:
	convertSchema.js
	group/_GroupMixin.js
	primitive/DateAttributeFactory.js
	primitive/SelectAttributeFactory.js
	primitive/StringAttributeFactory.js
	schema/refresolve.js
	tests/example_editor.html
	tests/meta/editor.json
	tests/meta/primitive_string.json
	tests/refresolve.js