Handle module re-export

[mycodedstuff]

Currently mExport doesn't handle re-exported modules.
Ideally in such cases the module would already have export list. We can read and preserve any exported modules in the export list. Next, we need remove the functions which are exported by the module.

Sample:
Expected

module A
  ( module B
  , foo
  ) where

import B (fn1, fn2)

foo :: String
foo = "Bar"

Actual

module A
  ( fn1
  , fn2
  , foo
  ) where

import B (fn1, fn2)

foo :: String
foo = "Bar"