feature(cloudcmd) add support of CLOUDCMD_ROOT (#64)

HELP.md

@@ -346,6 +346,7 @@ Some config options can be overridden with `environment variables` such:
 - `CLOUDCMD_AUTH` - enable authentication
 - `CLOUDCMD_USERNAME` - set username
 - `CLOUDCMD_PASSWORD` - set password
+- `CLOUDCMD_ROOT` - set root directory
 
 Menu
 ---------------

app.json

@@ -66,6 +66,11 @@
           "description": "set password",
           "value": "toor",
           "required": false
+      },
+      "CLOUDCMD_ROOT": {
+          "description": "set root dir",
+          "value": "",
+          "required": false
       }
   }
 }

bin/cloudcmd.js

@@ -57,7 +57,7 @@ const args = require('minimist')(argv.slice(2), {
         packer      : config('packer') || 'tar',
         zip         : config('zip'),
         username    : env('username') || config('username'),
-        root        : config('root'),
+        root        : env('root') || config('root'),
         prefix      : config('prefix'),
         progress    : config('progress'),
         console     : choose(env.bool('console'), config('console')),