message: Add class method binding docs
diff: @@ -543,3 +543,68 @@ function Vertibrates_Birds_Duck()
  end function
  ```
  </details>
  +
  +
  +## Instance binding
  +As you would expect, methods attached to a class will have their `m` assigned to that class instance whenever they are invoked through the object. (i.e. `someClassInstance.doSomething()`. However, keep in mind that functions themselves retain no direct knowledge of what object they are bound to.
  +
  +This is no different than the way plain BrightScript functions and objects interact, but it was worth mentioning that classes cannot mitigate this fundamental runtime limitation.
  +
  +Consider this example:
  +
  +```brighterscript
  +class Person
  + sub new(name as string)
  + m.name = name
  + end sub
  + sub sayHello()
  + print m.name
  + end sub
  +end class
  +
  +sub main()
  + m.name = "Main method"
  + bob = new SomeClass("bob")
  +
  + 'works as expected...the `m` reference is `bob`
  + bob.sayHello() 'prints "Bob"
  +
  + 'lift the function off of `bob`
  + sayHello = bob.sayHello
  +
  + '`m` is actually the global `m` scope
  + sayHello() ' prints "Main method"
  +end sub
  +```
  +<details>
  + <summary>View the transpiled BrightScript code</summary>
  +
  +```BrightScript
  +function __Person_builder()
  + instance = {}
  + instance.new = sub(name as string)
  + m.name = name
  + end sub
  + instance.sayHello = sub()
  + print m.name
  + end sub
  + return instance
  +end function
  +function Person(name as string)
  + instance = __Person_builder()
  + instance.new(name)
  + return instance
  +end function
  +
  +sub main()
  + m.name = "Main method"
  + bob = SomeClass("bob")
  + 'works as expected...the `m` reference is `bob`
  + bob.sayHello() 'prints "Bob"
  + 'lift the function off of `bob`
  + sayHello = bob.sayHello
  + '`m` is actually the global `m` scope
  + sayHello() ' prints "Main method"
  +end sub
  +```
  +</details>
  