Fix display rotation in terminal mode

[alvinhochun]

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Fix display rotation in terminal mode

Fix display rotation in terminal mode, referencing #145.

Only tested with a 96x16 display module.

[bugadani]

I can't confirm right now but I think the slight differences between this and #145 might not work for all displays. I'll try and check this week. Also pinging @jamwaffles just in case this PR had gone unnoticed.

[bugadani]

Actually, this seems to work just fine. Tested on 72x40, 96x16 and 128x32. I can also verify this PR actually fixing stuff because without it, my test app crashed hard :)

[jamwaffles]

Released in 0.5.2. Thanks for your patience!