config: Fix segfault

We can pass here NULL, win does not have a specific saved e_comp.
So we pass NULL to e_comp_get and get the current active one.

This fixes T1937.
add back notification merging

this was removed without warning or explanation in r82118:

    e: Change notification module to use internal notification API
    Patch by: José Roberto de Souza  <zehortigoza@profusion.mobi>

currently broken by T1954 for lines longer than 36 characters