[GTK] Title/subtitle usage

[AvtechScientific]

On the top bar (title bar) right now as title we have "gImageReader" and as subtitle - the input file name. Paths/filenames of the different tabs in the plain text output are not displayed.
Looking on gedit I'd suggest to remove "gImageReader" from the title (as it provides no important operational information to the user) and put the input file name as the title. (If you do want to keep "gImageReader in the title - one can choose the approach of Firefox and write something like this in the title - "My_input.pdf - gImageReader"). And as subtitle - use the full path to the currently highlighted tab in the plain text output panel. This is useful if you have the same file names in two different working directories. You can't distinguish them by the tab (file name) alone - full path in the subtitle will provide the information. I think this way you better make use of the top title bar space...