Log Message:
lxsession: update to 0.5.5

Remove libunique dependency, and use glib >= 2.28.0 to handle unique apps \ 
both for GTK+ 2 and 3.
Fix possible memory issue: use memmove instead of memcpy for overlapping area copy.
Fix memory issue: never free buffer returned by gtk_entry_get_text().
Fix spelling error: assiociate -> associate.
Pass desktop_environnement as a parameter for lxsession-xdg-autostart to fix \ 
wrong autostart processing.
Replace “images_display” with “image_display” for consistency.
Translations updates.