Add Maven Wrapper  #4

Prerequisites

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  • 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).