add .gitreview file

Change-Id: I7b59dec92aab1501665f5073aee24245fbbb537c
higan: fix DOWNLOADS temporarily

from the website:
    I have recently changed hosts. It will take me some time to rebuild the site here, so please be patient.

    In the mean time, you can access the old site at: byuu.net.

Change-Id: I3c7a17c1e82c5ea57b762de0117b27372c0a20a7