Rework displayio display bus transaction handling during refresh#1620

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dhalbert merged 3 commits intoadafruit:masterfrom

dhalbert:display-transactions-fix

Mar 7, 2019

Commits on Mar 6, 2019

check display-bus transaction status and act accordingly
dhalbert
committed

Commits on Mar 7, 2019

Rework background display task to allow reads from SPI SD card during display. Clarify code. Handle multiple displays better.
dhalbert
committed
Shrink build so de_DE fits
dhalbert
committed