Make background opened windows respect maximised states

Fixes issue 4037

Change-Id: I2d5096ef116b5e5325eb050c51a17cab4e5b867d
Reviewed-on: http://gerrit.dmdirc.com/1154
Automatic-Compile: DMDirc Local Commits <dmdirc@googlemail.com>
Reviewed-by: Chris Smith <chris@dmdirc.com>

Change-Id: I3372fcf5db4539d21192d663caaa052394377a2c
Reviewed-on: http://gerrit.dmdirc.com/276
Reviewed-by: Shane Mc Cormack <shane@dmdirc.com>
Tested-by: Gregory Holmes <greboid@dmdirc.com>