polymer upgrade
Merge branch 'master' of https://github.com/patefacio/finance

Conflicts:
	basic_input/lib/components/date_input.dart
	basic_input/lib/components/money_input.dart
	basic_input/lib/components/num_with_units_input.dart
	basic_input/lib/components/rate_input.dart
	basic_input/lib/components/year_input.dart
	basic_input/pubspec.yaml
	basic_input/web/examples/basic_input/basic_input.html
	mortgage_calculator/lib/components/mortgage_calculator.dart
	mortgage_calculator/lib/components/mortgage_details.dart
	mortgage_calculator/lib/components/payment_schedule.dart
	mortgage_calculator/pubspec.yaml
	mortgage_calculator/web/examples/mortgage_calculator/mortgage_calculator.html
regained and added imports for core-icon-button
per warning use better path for stylesheet import