[imp] Make the timer/scheduler to have precision alongside real-time speed

[arsdever]

Description

There are 2 types of timers:

• realtime_timer
• step_timer
  Each one of them has its own role. What is required is kind of the combination of those two timers: a timer, which runs in real time but also has a bigger precision. This is achievable with the introduction of fps in the scheduler's loop. With that, the scheduler tick will be triggered with custom frequency, and with each tick, a dedicated amount of timesteps may be simulated.

Expectation

It's possible to set real-time simulation speed and simulation accuracy.