Import address book

Dogecoin wallet offers export address book functionality, but it does not offer the import one. Users who want to use a new wallet and send dogecoins to the same users they already know have to re-enter their address manually to the sending addresses page.To alleviate Dogecoin wallet's users from from this hurdle, and to make the export/import functionality complete, I have added an "import" address book functionality to the sending addresses tab. The format of the imported file is the same as the exported files though the export functionality (csv files). Should this Pull Request be accepted?