Better regular expressions for CLI tests

[ndegory]

Refs #370

Rewrite of regexp to be more accurate

How to check:

swarm start
go test ./cmd/amp/cli

has to be rebased after #386 has been merged.

[subfuzion]

I think overall these look like good improvements. However, I'm not sure that changing the code to use posix character classes -- requiring an extra pair of enclosing brackets -- is worth the effort just for space, and without consensus and guidance, it's an arbitrary change on your part. I'm not opposed, although to me \s is just as readable and a lot less verbose than [[:space:]], and the nuances between perl and posix and non-ASCII support don't really matter here. Of course, once you move beyond \s, '\d, \w classes, [[:alnum:]], [[:alpha:]], [[:blank:]], [[:lower:]], [[:punct:]], [[:upper:]], and [[:xdigit:]] become more readable. On that note, I wonder if we're accepting [[:space:]] in cases where [[:blank:]] is more appropriate? Anyway, we'll move all these into a standard regex dictionary and we can fine tune as needed. Thanks.

[subfuzion]

@ndegory Please resolve conflicts so this can be merged. @bquenin's PR renamed the associated files.

[ndegory]

@subfuzion I'll revert the [[:space:]] to \s if you prefer, anyway it's anecdotal, the main change is that the regexp now are matching different outputs.

[subfuzion]

👍