Add variable and parameter to adjust the intensity and duration of the buttplug

[Cheemsandfriends]

This adds a variable and a function parameter:

• The intensity variable, where you can select your intensity without having to hardcode it each time and make the vibration more or less powerful depending on the situation

• The duration parameter inside vibrate(), where you can select the amount of milliseconds the vibrations are going to be present.

[GsDrunkestDriver]

Thanks!