[FEATURE] Easy access to conventional tape speeds

[jatinchowdhury18]

From KVR/Sink:

• Also, would it be possible to have (maybe optional?) stepped values for the tape speeds (so we would have 3,3/4 > 7.5 > 15 ips etc, and we would avoid thousands of intermediate values like 14,0145, etc).

Is your feature request related to a problem? Please describe.
Although the plugin allows tape speed to be varied continuously, it would be niceto be able to quickly access conventional tape speeds (3.75, 7.5, 15 ips).

Describe the solution you'd like
My plan is to add three buttons either above or below the slider that will snap the slider to the corresponding value.

[jatinchowdhury18]

The buttons for snapping the slider to the desired values will look like this: