Improvements:
* improved test for PaymentCardTextField component
* added Spoiler component and testID util in example project
* updated root and example project structure
* created build scripts
* added tipsi eslint config
* other small improvements
* Updated local-ci script and travis script to init new example project and link library
* Removed example_tmp project
* Fix iOS example build command
* Copy build.gradle to temp example project
* Fixed Travis before-install script
* Travis possible fix
* God-like fix for copy script
* Add settings.gradle into cp pipeline
* Some fixes for local-ci script
* Fixed local-ci script
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for local-ci script
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Some fixes for Travis scripts
* Improvements for local-ci and Travis scripts
* Fixed iOS post-link script
* Some fixes in ci scripts
* Fixed naming for macOS in CI scripts
* Freeze Stripe version for iOS and Adnroid