docs: update README.md with babel configuration info (#860)

dmwelch · bcoe · commit f0d98a548926 · 2018-06-07T17:52:17.000-07:00
diff --git a/README.md b/README.md
@@ -103,7 +103,7 @@ project uses the babel tool chain:
     }
   ```
 
-  Note: With this configuration, the Istanbul instrumentation will only be active when `NODE_ENV` or `BABEL_ENV` is `test`.
+  Note: With this configuration, the Istanbul instrumentation will only be active when `NODE_ENV` or `BABEL_ENV` is `test` unless the environment is a valid entry in `"env"` within the `.babelrc` file.
 
   We recommend using the [`cross-env`](https://npmjs.com/package/cross-env) package to set these environment variables
   in your `package.json` scripts in a way that works cross-platform.

Original file line number	Diff line number	Diff line change
`@@ -103,7 +103,7 @@ project uses the babel tool chain:`
`103`	`103`	`}`
`104`	`104`	```
`105`	`105`
`106`		- Note: With this configuration, the Istanbul instrumentation will only be active when `NODE_ENV` or `BABEL_ENV` is `test`.
	`106`	+ Note: With this configuration, the Istanbul instrumentation will only be active when `NODE_ENV` or `BABEL_ENV` is `test` unless the environment is a valid entry in `"env"` within the `.babelrc` file.
`107`	`107`
`108`	`108`	We recommend using the [`cross-env`](https://npmjs.com/package/cross-env) package to set these environment variables
`109`	`109`	in your `package.json` scripts in a way that works cross-platform.