See https://golang.org/pkg/sync/atomic/#pkg-note-BUG for reference:
"The first word in (...) an allocated struct (...) can be relied up to
be 64-bit aligned"
This fixes an "unaligned 64-bit atomic operation" panic on 32-bit ARM,
(in my case a Raspberry Pi 4, running 32-bit Raspbian). The panic
happens (at least) during the first login after a service (re)start.
rollback indexer map
use sync.pool for cache entries
add tests for cache
remove main locks from nrwmutex and use sync.map and sync.pool instead
bump dockerfile go version