Enable the custom logo feature

[mattmary]

for now this feature is disabled in https://github.com/matomo-org/matomo-for-wordpress/blob/develop/config/common.config.ini.php#L18. we need a feature in Matomo for WordPress to customise the path where the logo should be uploaded to and also an option to change the URL to the path so it would be loaded eg from the wp-content/uploads directory

I believe when you upload a logo in Matomo it tries to upload it to app/misc/user. And I believe this directory can currently not be changed. If we were to upload it in there, the next time they update the WordPress plugin the uploaded logo may be gone. Meaning we would first need a feature in Matomo for WordPress to customise the path where the logo should be uploaded to and also an option to change the URL to the path so it would be loaded eg from the wp-content/uploads directory.