Tests

minor doc cleanup #113

Job	Run time
windows-latest (R-release rust-stable-msvc)	9m 24s
windows-latest (R-devel rust-stable-msvc)	8m 46s
windows-latest (R-oldrel rust-stable-msvc)	12m 23s
macOS-latest (R-release rust-stable)	6m 6s
ubuntu-latest (R-release rust-stable)	1m 2s
ubuntu-latest (R-release rust-nightly)	4m 56s
ubuntu-latest (R-devel rust-stable)	17m 28s
ubuntu-latest (R-oldrel rust-stable)	1m 13s
ubuntu-latest w/ bindgen (R-devel rust-stable )	4m 34s
macOS-latest w/ bindgen (R-devel rust-stable )	8m 11s
windows-latest w/ bindgen (R-release rust-stable-msvc x86_64-pc-windows-gnu)	6m 47s
windows-latest w/ bindgen (R-devel rust-stable-msvc x86_64-pc-windows-gnu)	8m 35s
windows-latest w/ bindgen (R-release rust-nightly-msvc x86_64-pc-windows-gnu)	7m 23s
windows-latest w/ bindgen (R-oldrel rust-nightly-msvc x86_64-pc-windows-gnu)	8m 25s
	1h 45m 13s

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