* Logging and startup improvements
Color support for released binaries!
* startup scripts no longer log to file by default - this only affects
source builds - released binaries don't support file logging
* add --log-stdout option to control logging to stdout (colors, json)
* detect tty:s vs redirected logs and log accordingly
* add option to disable log colors at runtime
* simplify several "common" logs, showing the most important information
earlier and more clearly
* remove line numbers / file information / tid - these take up space and
are of little use to end users
* still enabled in debug builds and tools
* remove `testnet_servers_image` compile-time option
* server images, released binaries and compile-from-source now offer
the same behaviour and features
* fixes https://github.com/status-im/nimbus-eth2/issues/2326
* fixes https://github.com/status-im/nimbus-eth2/issues/1794
* remove instanteneous block speed from sync message, keeping only
average
before:
```
INF 2021-10-28 16:45:59.000+02:00 Slot start topics="beacnde" tid=386429 file=nimbus_beacon_node.nim:884 lastSlot=2384027 wallSlot=2384028 delay=461us84ns peers=0 head=75a10ee5:3348 headEpoch=104 finalized=cd6804ba:3264 finalizedEpoch=102 sync="wwwwwwwwww:0:0.0000:0.0000:00h00m (3348)"
INF 2021-10-28 16:45:59.046+02:00 Slot end topics="beacnde" tid=386429 file=nimbus_beacon_node.nim:821 slot=2384028 nextSlot=2384029 head=75a10ee5:3348 headEpoch=104 finalizedHead=cd6804ba:3264 finalizedEpoch=102 nextAttestationSlot=-1 nextProposalSlot=-1 nextActionWait=n/a
```
after:
```
INF 2021-10-28 22:43:23.033+02:00 Slot start topics="beacnde" slot=2385815 epoch=74556 sync="DDPDDPUDDD:10:5.2258:01h19m (2361088)" peers=37 head=eacd2dae:2361096 finalized=73782:a4751487 delay=33ms687us715ns
INF 2021-10-28 22:43:23.291+02:00 Slot end topics="beacnde" slot=2385815 nextActionWait=n/a nextAttestationSlot=-1 nextProposalSlot=-1 head=eacd2dae:2361096
```
* fix comment
* documentation updates
* mention `--log-file` may be deprecated in the future
* update various docs
* "official" -> "scenarios", like the submodule
* fewer test binaries - various compile hacks have been improved over
time, test suite should follow
* remove obsolete bls tests - there are better test vectors in
nim-blscurve
* remove obsolete mentions of `ssz_testing`
* remove obsolete comments about proc vs globals, unittest2 already uses
proc's
* re-add minimal preset constant checking; organize presets to better support multiple spec versions
* bump spec ref
* increase Azure timeout to 90 minutes to accomodate Nim compiler building
* update test submodule [skip ci]
* rename the process_lfs script to setup_official_tests [skip ci]
* clarify that the existing LFS is for json files [skip ci]
* Update again to use download/unpack function library
* update the test downloading script [skip ci]
* Update EF fixtures with new test path
* fix symlink order
* Fix relative:absolute symlink issue
* add symlink existence check
* setup_official_tests.sh: refactoring
Jacek Sieka
Zahary Karadjov
tersec
Ștefan Talpalaru
Mamy Ratsimbazafy