task/CR-1401-extended-themes-before-ls-6-can-cause-issue-with-the-attributes-when-generating-xml-files

[marticos]

Fixed issue Jira ticket:
https://limesurvey.atlassian.net/browse/CR-1401

This PR fixes an issue discovered during the copying or the exportation of a survey that is using a template with an invalid config file. To reproduce the issue please create a theme with the invalid cssframework node in the config file, like so.

`

        <dropdownoptions>
                <option data-mode="replace" value="css/variations/basic.min.css">Basic Bootstrap</option>
                <option data-mode="replace" value="css/variations/cerulean.min.css">Cerulean</option>
                <!-- ...more options -->
                <option data-mode="replace" value="css/variations/yeti.min.css">Yeti</option>
        </dropdownoptions>
    </cssframework>`

These kind of files will also produce invalid values in the database table template_configuration, specifically the @Attribute value in the option column that will throw an error during the creation of files to be exported.

These changes will scan all the configuration.xml files and the database to fix the values.
This also adds a check whenever an action is being triggered upon a template config file, to check his integrity.

To test the PR, please first reproduce the error by importing a few theme with an invalid config files, then perform the update to version 624 and try to export or copy the surveys that had the invalid data.