Make Settings more closely align with command-line flags
and environment variables.
- Change command-line flags to begin with -
- Change syntax of build lines to use Key=Value instead of Key<tab>Value.
- Change CGO_ENABLED to 0/1, matching environment variable,
instead of false/true.
- Add GOOS and GOARCH.
These are technically redundant, in that they can be extracted
from the binary in other ways most of the time, but not always:
GOOS=ios and GOOS=darwin may produce binaries that are
difficult to tell apart. In any case, it's a lot easier to have them
directly in the settings list than derive them from other parts
of the binary.
- Add GOEXPERIMENT.
These could be inferred from the tags list, but the experiments
are being removed from the tags list.
- Change the tags list to match the -tags command-line argument.
- Add msan and race, echoing the -msan and -race arguments
(always 'true' when present, omitted when false).