concurrency: update shared resource examples#196

Merged

bors[bot] merged 3 commits intorust-embedded:masterfrom geomatsi:mut-shared-wip

Jul 11, 2019

+60

Commits on Jul 9, 2019

concurrency: example of mutable reference to shared resource
geomatsi
committed
concurrency: add note about const-fn feature in cortex-m crate
geomatsi
committed

Commits on Jul 11, 2019

fixup: address review comments
geomatsi
committed