Add export and import functionality

[zepich]

Discussed in #108

^{Originally posted by Digi92 June 26, 2023}
Hi,
i think a function to copy an existing project would be nice.
A user might want to copy an existing project with all settings, rules and rule sets to use this as a basis for a new project.

To consider would be of course how the rights should look like.

What is your opinion about this?

Idea

Export functionality

• Add an option to export a project's settings into a file. This includes all project settings (Name, Description, Hosts, Spam rating factor, security settings, design settings, all rules with all items, and all rulesets). It does not include submissions, project members, and the API keys as well as the project UUID.
• The user can choose which parts should be included in the export. For example, general project data (Name, Description, Hosts, Spam rating factor), security settings, design settings, rules, or rulesets.
• The user will download a JSON file with the selected data.

Import functionality

• Add an option to import a project's settings from a file.
• The user can choose which parts should be imported from the provided file. For example, the user can only import rules, not other things in the file.
• The user can choose what the import process should do with existing rules. The user can either override the existing rules (remove additionally available items), append the not existing items to the existing rule, or add the rule as a new rule. All other data will be replaced if selected for import (project settings and rulesets).

Changes

• Add the schema for the configuration file to the mosparo Specifications
• Add the export functionality in the tools area
• Add the import functionality in the tools area
• Add a button (to go to the import functionality) in the project wizard to import directly (without going through all the wizard steps)
• Add two commands to export and import the settings via CLI

Suggested by

• @Digi92