Merge pull request #835 from zcash/halo2_poseidon-0.1.0 #4083

Job	Run time
Book tests	1m 24s
Bitrot check	1m 25s
Code coverage	3m 27s
Build target wasm32-unknown-unknown	1m 51s
Build target wasm32-wasi	1m 37s
Test on ubuntu-latest	7m 27s
Test on i686-unknown-linux-gnu	13m 13s
Test on windows-latest	10m 38s
Test on i686-unknown-linux-gnu with beta features	13m 28s
Test on macOS-latest	6m 46s
Test on i686-unknown-linux-gnu with nightly features	15m 26s
Test on ubuntu-latest with beta features	7m 17s
Test on windows-latest with beta features	11m 5s
Test on macOS-latest with beta features	6m 19s
Intra-doc links	1m 29s
Test on ubuntu-latest with nightly features	8m 33s
Test on windows-latest with nightly features	11m 27s
Test on macOS-latest with nightly features	8m 11s
Rustfmt	14s
	2h 11m 17s

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