Luci js app -- how to handle long-ish (60+ seconds) rpcd request

@jow -- I want to implement the pause button in luci-app-adblock-fast. From CLI I've added a pause function to the init script and it essentially stops service, sleeps for N seconds and then starts the service and it works well.

If I try to just call setInitAction with pause command from the js file, it just stays on the modal popup forever.

How to handle this gracefully from the luci app?

This is the status.js with the button: https://github.com/stangri/source.openwrt.melmac.net/blob/master/luci-app-adblock-fast/htdocs/luci-static/resources/adblock-fast/status.js#L350-L363

This is the rpcd script: https://github.com/stangri/source.openwrt.melmac.net/blob/master/luci-app-adblock-fast/root/usr/libexec/rpcd/luci.adblock-fast#L126-L147

Thanks!