Create a plugin system

- Add feedback on errors
- More generic import requests
- Replace storing password by a native popup that ask passwork when needed
- Store passwords in settings file
- Import Feedback in advanced settings tab
- Use English as default translator if no translations are found
- Add OpenSSL packaging for Windows to deal with Qt connections
- Add option to overwrite plugin if exists
- Plugin load/unload managment. Hot-Dynamic load of plugins. Safely test the loaded plugin
- Set plugin data with default value when all GUI items are loaded
- Rewrite folder priority
- Add filename info from pluginloader
- Add plugin versionning
- Specify inputs for saving
- Copy desktop headers in OUTPUT to be used by external projects
- Add a plugins folder auto-managed by cmake
- Remove obsolete contact api submodule
- Clean plugin example
- Add specific behaviour for plugin type : inputs have been splitted by Capability.
- Update save/load to be more generic and add clean function for configurations
- Instantiate Importer List model
- Add IDE integration for plugins
- Set input fields to be dependent of capability
- Change signals interface to take account capability