[bgo#625782] Importing of files to TM more verbosed

[mrkara]

While importing files to translation memory and after is completed should appear on dialog showing the progress or changes done at the data base.

After the import should be showed one dialog indicating a summary that contains:

• how many files were imported
• how many strings were imported
• little resume of the state of the data base:
  • total entries at database
  • strings before import

Originally reported by Fran Diéguez at https://bugzilla.gnome.org/show_bug.cgi?id=625782

[mrkara]

Changed the severity to «enhancement».

We'll try to review it.

Originally posted by Daniel Mustieles