fix assemble
be more descriptive on destroy about which machine
have to be particular about how we forward bash args or they aren't
properly delimited in quotes for process.argv
one way i came up with for minimalist argument parsing before i
realized the real problem was how i was forwarding the arguments
through bash; can be simpler than this, but this is still cool
simplify bash argument parsing
allow users to pass CSON via --locals cli argument

valid examples:

borg assimilate aws-or-prod-mybox01.mydomain.tld \
  --locals ssh:port:1234
borg assimilate aws-or-prod-mybox01.mydomain.tld \
  --locals '{ "ssh": { "port": 22202 } }'
borg assimilate aws-or-prod-mybox01.mydomain.tld \
  --locals '{ ssh: { port: 22202 } }'
simplify regexp match parsing using non-matching groups