Fix to passphrase dialog and Issue #207

As you have asked, I have added 'bottom margin' to table row in "Passphrase Dialog", So users do not accidentally press 'Cancel' or 'Ok' button.
Regarding Issue #207,  I have attempted to solve it.
Parameters are: Master Key Id (Hex Format), User Name , User Email

https://drive.google.com/file/d/0B31e8A3Srhc3SThOSjBUSDRzcWs/edit?usp=sharing

Let me know if any changes are required.

2nd Commit: Implemented View Holder Pattern for ImportSettingsKeyAdapter.