Doc crypto #484

Job	Run time
afl-build	4m 44s
all-features	1m 18s
build (linux)	1s
long-tests	4m 7s
test-bindings-c-cpp-linux	48s
build (macos)	1s
test-bindings-c-cpp-windows (Debug-c, x86_64-pc-windows-msvc)	2m 25s
build (windows)	1s
test-bindings-c-cpp-windows (Debug-c, i686-pc-windows-msvc)	2m 32s
audit	8s
test-bindings-c-cpp-windows (Release-c, x86_64-pc-windows-msvc)	2m 18s
test-bindings-c-cpp-windows (Release-c, i686-pc-windows-msvc)	2m 19s
clippy	3m 44s
test-bindings-c-cpp-windows (Debug-cpp, x86_64-pc-windows-msvc)	2m 19s
test-bindings-c-cpp-windows (Debug-cpp, i686-pc-windows-msvc)	2m 21s
fmt	4s
test-bindings-c-cpp-windows (Release-cpp, x86_64-pc-windows-msvc)	1m 49s
test-bindings-c-cpp-windows (Release-cpp, i686-pc-windows-msvc)	2m 13s
publish-dry-run	5s
	33m 17s

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