Created by: NotBikappa
The goal of this PR is to give precedence to the headers defined by the aem_hacker script over the extra headers passed as command line arguments.
In some scenario the user might need to configure the 'Authorization' header because his target environment is protected with basic authentication, for example.
The aem_hacker scripts also need to configure that header for some checks, aiming to test the configuration with default credentials.
If the user defined headers are used those checks are not effective