feature request: watch .env file

[obedm503]

this is a really cool plugin, but it's missing a huge feature for me. when I update the .env file, webpack-dev-server doesn't trigger a recompilation and the environment variables in the source code don't update.

for example, while developing a client side app I might have a local server and a cloud server, and I might change which server is used depending on which data I want to display

# local server
API=localhost:8080/api/
# cloud server
# API=https://example.com/api/

changes

# local server
# API=localhost:8080/api/
# cloud server
API=https://example.com/api/

is this possible?