Suggestion for cross platform development script

[ZQ-jhon]

Behavior:

Some code fragment in package.json:

{
...
start: NODE_ENV = XXX  gulp build
...
}

And when i input npm run start by PowerShell, will get error:

`'NODE_ Env 'is not an internal or external command, nor a runnable program

Suggestion:

Adding a package named "cross-env" for resolve cross platform script building.

{
...
start: cross-env NODE_ENV = XXX  gulp build
...
}