Request for non-blocking duration timers

[stijnpiron]

At this moment, the delay for the LED is blocking the program to continue it's loop.
I'm using this library to get a status led flashing in multiple colors, works like a charm.
But in the meantime, I want the webserver running to respond to my requests without having to wait for the delays to complete.
For example: I have one status led that flashes 100ms every 30s, when performing a webserver request, I have to wait up to 30s for it to respond as this library is blocking everything.