Generate one-liner with insecure flag

[javuto]

Implementation the fix for #237 and adding the possibility to generate one-liners with the insecure flag:

USAGE:
   osctrl-cli environment quick-add [command options] [arguments...]

OPTIONS:
   --name value, -n value    Environment to be used
   --target value, -t value  Type of one-liner (default: "sh")
   --insecure, -i            Generate insecure one-liner (default: false)
   --help, -h                show help (default: false)