Android-runtime: Improve TypeScript definitions generation

[atanasovg]

Following are the issues with the current definitions of the available Android APIs:

• #15
• #78

Additionally, there are quite some declarations that are manually put into the android17.d.ts file, which is error prone and should be automated.

[Plamen5kov]

iOS has a method to enable d.ts file generation as a build step, which slows down the build and generates a separate d.ts file for each module. We should enable the same functionality in android and it's worth thinking about a CLI flag that enables build with d.ts generation.

[petekanev]

The issues have been addressed in one way or another.

As of 2.4 typings for the Android SDK and all android support libraries, dependencies of the project, can be enabled by specifying an additional flag when building/running a NativeScript project.

Should we close this now?

[Plamen5kov]

Until typescript allows us to represent java generic with anything different than any and the namespace scopes are better recognized by tsc, there's little more we can improve.