more CI tweaks (#11) #279

Job	Run time
Test Rust 1.60.0 on ubuntu-latest	1m 59s
Check warnings	12s
Test Rust stable on ubuntu-latest	21s
Test Rust stable on macos-latest	23s
coverage	36s
Test Rust stable on windows-latest	51s
Test on i686-unknown-linux-gnu (using cross)	1m 9s
Verify code formatting	14s
Test Rust stable-i686-msvc on windows-latest	1m 19s
Test on armv7-linux-androideabi (using cross)	1m 30s
Test Rust beta on ubuntu-latest	23s
Test on aarch64-unknown-linux-gnu (using cross)	1m 31s
Test Rust nightly on ubuntu-latest	23s
Test on powerpc-unknown-linux-gnu (using cross)	1m 13s
Test on powerpc64-unknown-linux-gnu (using cross)	1m 14s
	13m 18s

Provide feedback