Move context identifier to the front

[mbrodala]

Right now the context identifier (local, dry-run or none) must be passed as last word after a command but before the arguments of the command, e.g.

nanobox evar add local ENVIRONMENT=local MY_EVAR="This is mine"

It is very easy to forget this very specific and special rule and misplace the local here.

This is why I suggest to move the context identifier right after the nanobox command:

nanobox local evar add ENVIRONMENT=local MY_EVAR="This is mine"

This way it is clear right away what context a command is executed in and I suspect that argument parsing and command processing can be simplified too.

Here's an example from Composer:

composer require foo/bar # Install a package locally
composer global require foo/bar # Install a package globally

Even though the logic is different (local by default, global/remote as special case) it is clear right away what will happen and it's easy to remember.