improve test display, preserve artifacts

- when tests fail, store artifacts from initial run in failed-tests.tar
- store the original test summary output
- after retry, display both the original and the new test summary
- tweak echo_i and cat_i functions to get output spacing and colors right
39 jobs for !1428 with each-test-retry in 11 minutes and 51 seconds (queued for 4 seconds)
latest detached
Status Job ID Name Coverage
  Precheck
passed #170077
linux amd64
🐞:sid:amd64

00:00:37

passed #170076
linux amd64
misc:sid:amd64

00:00:15

 
  Build
passed #170088
linux amd64
asan:sid:amd64

00:01:19

passed #170089
linux amd64
clang:stretch:amd64

00:01:12

passed #170090
linux i386
clang:stretch:i386

00:01:11

passed #170078
linux amd64
docs:sid:amd64

00:00:44

passed #170087
linux amd64
gcc:bionic:amd64

00:01:53

passed #170079
linux amd64
gcc:centos6:amd64

00:02:20

passed #170080
linux amd64
gcc:centos7:amd64

00:01:52

passed #170085
linux amd64
gcc:fedora29:amd64

00:01:59

passed #170081
linux amd64
gcc:jessie:amd64

00:01:36

passed #170083
linux amd64
gcc:sid:amd64

00:02:02

passed #170084
linux i386
gcc:sid:i386

00:01:53

passed #170082
linux amd64
gcc:stretch:amd64

00:01:54

passed #170086
linux amd64
gcc:xenial:amd64

00:01:53

passed #170091
linux amd64
pkcs11:sid:amd64

00:01:04

 
  Test
passed #170110
linux amd64
system:asan:sid:amd64

00:07:02

passed #170108
linux amd64
system:gcc:bionic:amd64

00:08:52

passed #170092
linux amd64
system:gcc:centos6:amd64

00:06:29

passed #170094
linux amd64
system:gcc:centos7:amd64

00:06:04

passed #170104
linux amd64
system:gcc:fedora29:amd64

00:07:59

passed #170096
linux amd64
system:gcc:jessie:amd64

00:06:54

passed #170100
linux amd64
system:gcc:sid:amd64

00:06:42

passed #170102
linux i386
system:gcc:sid:i386

00:06:25

passed #170098
linux amd64
system:gcc:stretch:amd64

00:06:56

passed #170106
linux amd64
system:gcc:xenial:amd64

00:06:45

passed #170113
linux amd64
system:pkcs11:sid:amd64

00:06:38

passed #170111
linux amd64
unit:asan:sid:amd64

00:00:59

passed #170112
linux amd64
unit:clang:stretch:amd64

00:00:44

passed #170109
linux amd64
unit:gcc:bionic:amd64

00:00:49

passed #170093
linux amd64
unit:gcc:centos6:amd64

00:00:43

passed #170095
linux amd64
unit:gcc:centos7:amd64

00:00:54

passed #170105
linux amd64
unit:gcc:fedora29:amd64

00:00:54

passed #170097
linux amd64
unit:gcc:jessie:amd64

00:00:41

passed #170101
linux amd64
unit:gcc:sid:amd64

00:00:49

passed #170103
linux i386
unit:gcc:sid:i386

00:00:43

passed #170099
linux amd64
unit:gcc:stretch:amd64

00:00:44

passed #170107
linux amd64
unit:gcc:xenial:amd64

00:02:03

passed #170114
linux amd64
unit:pkcs11:sid:amd64

00:01:55