differentiate Kotlin generic type parameters

[btwilk]

Is your enhancement request related to a problem? Please describe.
It can be hard differentiate a standard type (e.g., interface/class) and a generic type parameter.

class Container<Element> {
  ...
  // lots of stuff
  ...
  fun foo(e: Element) { // looking only here it is not clear that Element is a generic type parameter
    ...
  }
  ...
}

Describe the solution you'd like
Give generic type parameters a distinct color from interfaces/classes.

Additional context

• IntelliJ does this by default.
• Java/Kotlin programmers conventionally use single-letter parameter names for generics. This is evidence that it is important to distingush them from interfaces/classes.
• If syntax highlighting can help with this differentiation, then there is less motivation to purposely use bad parameter names like E.