Add Maven Wrapper

[dortegau]

Prerequisites

• Put an X between the brackets on this line if you have done all of the following:
  • Checked that your issue isn't already filled: https://github.com/issues?utf8=✓&q=is%3Aissue+user%3Aidealista
  • Checked that there is not already provided the described functionality

Description

Add Maven Wrapper (https://github.com/takari/maven-wrapper) to integrate Maven and avoid the need to have and specific version of Maven installed

Expected behavior:

Execute Maven goals using the embedded Maven Wrapper:

$ ./mvnw test

Actual behavior:

Actually requires an external installation of Maven with a specific version (Maven 3.3.3 or higher).