[ipad-app] Add library redesign

[todor]

• instead of the current dialog the following process should be applied when adding new libraries
  • instead of plus there should be a different button (for now it's going to be only a label "Libraries")
  • when the user clicks on it, list similar to the one that is shown in appstore and safari search will appear (see the capture.png)
    • the user is presented with list of all his/hers added libraries
    • the user can select library by tapping on its name
    • there should be a "Add" button, similar to the green button in the left-hand side of capture.png (the button should be default blue button labeled "Add")
    • when the user taps on the "Add" button a dialog similar to the one in secondscreen.png should appear
    • the fields should be "name" and "url" and the buttons should be ok and cancel