QUIC: Update README and CHANGES for 3.1.7 #356

Job	Run time
run-checker (no-atexit)	4m 40s
run-checker (no-cmp)	4m 7s
run-checker (no-cms)	4m 12s
run-checker (no-ct)	4m 25s
run-checker (no-dtls)	4m 22s
run-checker (no-ec)	3m 46s
run-checker (no-ec2m)	4m 9s
run-checker (no-legacy)	4m 17s
run-checker (no-rfc3779)	4m 24s
run-checker (no-sock)	4m 5s
run-checker (no-srp)	4m 21s
run-checker (no-srtp)	4m 22s
run-checker (enable-ssl-trace)	4m 26s
run-checker (no-tests)	2m 12s
run-checker (no-threads)	4m 17s
run-checker (no-tls)	4m 8s
run-checker (no-tls1_2)	4m 20s
run-checker (no-tls1_3)	4m 27s
run-checker (enable-trace enable-fips)	4m 43s
run-checker (no-ts)	4m 37s
run-checker (no-ui)	4m 20s
	1h 28m 40s

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