Add and remove individual templates without resetting the model
- Add the individual templates to the model without first clearing the model
- Add a function to the abstract model to remove a node
- Remove a template without clearing and re-adding the rest
- Remove the "Success" message dialogs as the result is quite obvious also without them
- Move userTemplatePath() to be a local static function in template.cpp
- Rename onRemoveClicked() to removeTemplate() to align with the previous import and export functions
@sahilvermaiiitmg do you want to have a look?