fix issue #369 by changing 'Model' to 'Record'

This changes the following text for issue #369 :
* models were successfully deleted. -> records were successfully deleted.
* Model was successfully saved. -> Record was successfully saved.
* Model was successfully created. -> Record was successfully created.
* Model was successfully deleted. -> Record was successfully deleted.
* Failed to update model. -> Failed to update record.
* Failed to create model. -> Failed to create record.
* Failed to delete model. -> Failed to delete record.
* Failed to delete models. -> Failed to delete records.
* Are you sure you want to delete selected models? -> Are you sure you want to delete selected records?
* Please select at least one model. -> Please select at least one record.

Some of the translations will also need to change after this.