removed the sidepane title

Based on FR commit: 55a12cb2adfc818b5b659cbcf003e80a7fc89da8
From: Paolo Bacchilega <paobac@src.gnome.org>
Update POTFILES.in
enable interactive search in the file list

Based on FR commit: 574906a243f7bb8b2b63654d9b0be91fe2bcf738
From: Paolo Bacchilega <paobac@src.gnome.org>
do not update if the progress dialog is null

Based on FR commit: be63c259099367a73332be59b5bcee4d0c6519f1
From: Paolo Bacchilega <paobac@src.gnome.org>