Fix some .desktop files getting deleted

I updated one of the EasyOS installations, and Firefox disappeared from the menu. The /usr/share/applications/firefox.desktop file had reverted to containing "NoDisplay=true".

There are other possible situations where a .desktop file might get inappropriately deleted.

I have studied the code and made improvements. See commit:

https://github.com/bkauler/woofq/commit/edc72720126c133405c5923849774843688483d8

...which seems like it will improve the situation.    

Tags: easy