Add keywords to .desktop files to thunar (bug #16618)

thunar-bulk-rename.desktop.in.in

@@ -2,6 +2,7 @@
 _Name=Bulk Rename
 _Comment=Rename Multiple Files
 _GenericName=Bulk Rename
+_Keywords=bulk;renamer;renaming;thunar;files;folders;directory;directories;
 Exec=thunar --bulk-rename %F
 Icon=Thunar
 Terminal=false

thunar.desktop.in.in

@@ -2,6 +2,7 @@
 _Name=Thunar File Manager
 _Comment=Browse the filesystem with the file manager
 _GenericName=File Manager
+_Keywords=file manager;explorer;finder;browser;folders;directory;directories;partitions;drives;network;devices;rename;move;copy;delete;permissions;home;trash;
 Exec=thunar %F
 Icon=Thunar
 Terminal=false

thunar/thunar-settings.desktop.in

@@ -2,6 +2,7 @@
 Version=1.0
 _Name=File Manager Settings
 _Comment=Configure the Thunar file manager
+_Keywords=thunar;settings;preferences;configure;thumbnails;file size;date format;shortcuts pane;tree view;tabs;
 Exec=thunar-settings
 Icon=system-file-manager
 Terminal=false