* fix(android/action-bar): process Icon Fonts in NavigationButton the same way as in ActionItem
* Add NavigationButton with font icons to corresponding page in ui tests app
* feat(platform-declarations): generate typings from iOS 13.0 SDK
* fix(platform-declarations): typings generation script
Delete Material Components typings from `tns-platform-declarations`,
they are part of `tns-core-modules` package.
* refactor(platform-declarations): workaround a TypeScript error
Error:
```
tns-platform-declarations/ios/objc-x86_64/objc!OSLog.d.ts(178,15): error TS2417: Class static side 'typeof OSLogEnumerator' incorrectly extends base class static side 'typeof NSEnumerator'.
Types of property 'alloc' are incompatible.
Type '() => OSLogEnumerator' is not assignable to type '<ObjectType>() => NSEnumerator<ObjectType>'.
Type 'OSLogEnumerator' is not assignable to type 'NSEnumerator<ObjectType>'.
Types of property 'allObjects' are incompatible.
Type 'NSArray<NSObject>' is not assignable to type 'NSArray<ObjectType>'.
Type 'NSObject' is not assignable to type 'ObjectType'.
'NSObject' is assignable to the constraint of type 'ObjectType', but 'ObjectType' could be instantiated with a different subtype of constraint '{}'.
```
References:
https://github.com/Microsoft/TypeScript/issues/17575https://stackoverflow.com/questions/52518125/workaround-for-accessing-class-type-arguments-in-static-method-in-typescript
* docs(platform-declarations): note a manual step on generating typings
* chore(platform-declarations): exclude ios-typings-prj from transpilation
* refactor(platform-declarations): delete references to MDC types
```
ios/objc-x86_64/objc!QuartzCore.d.ts:676:36 - error TS2304: Cannot find name 'MDCAnimationTimingFunction'.
676 static mdc_functionWithType(type: MDCAnimationTimingFunction): CAMediaTimingFunction;
ios/objc-x86_64/objc!UIKit.d.ts:7717:54 - error TS2304: Cannot find name 'MDCFontTextStyle'.
7717 static mdc_preferredFontForMaterialTextStyle(style: MDCFontTextStyle): UIFont;
ios/objc-x86_64/objc!UIKit.d.ts:7719:53 - error TS2304: Cannot find name 'MDCFontTextStyle'.
7719 static mdc_standardFontForMaterialTextStyle(style: MDCFontTextStyle): UIFont;
ios/objc-x86_64/objc!UIKit.d.ts:7771:63 - error TS2304: Cannot find name 'MDCFontTextStyle'.
7771 mdc_fontSizedForMaterialTextStyleScaledForDynamicType(style: MDCFontTextStyle, scaled: boolean): UIFont;
ios/objc-x86_64/objc!UIKit.d.ts:7794:64 - error TS2304: Cannot find name 'MDCFontTextStyle'.
7794 static mdc_preferredFontDescriptorForMaterialTextStyle(style: MDCFontTextStyle): UIFontDescriptor;
ios/objc-x86_64/objc!UIKit.d.ts:7796:63 - error TS2304: Cannot find name 'MDCFontTextStyle'.
7796 static mdc_standardFontDescriptorForMaterialTextStyle(style: MDCFontTextStyle): UIFontDescriptor;
```
