[AESH-255] The project should to have gradle wrapper

The Gradle Wrapper (henceforth referred to as the “wrapper) is the preferred way of starting a Gradle build. The wrapper is a batch script on Windows, and a shell script for other operating systems. When you start a Gradle build via the wrapper, Gradle will be automatically downloaded and used to run the build.

http://www.gradle.org/docs/current/userguide/gradle_wrapper.html