Splitting linear * read without jailing type checks

The line **TYPE CHECKS** below should not. 

```
read trait T

read trait Get
  require val value:T
  def gett() : T
    this.value

linear trait Set
  require value:T
  def set(v:T) : void
    this.value = v

passive class Cell : Get + Set
  value:T

class Main
  object:Cell
  def main() : void
    let
      g : Get, w : Set = consume this.object  ---- TYPE CHECKS!
    in
      ()
```
