message: Update Ext Readme
  About a nice CMake script for the sRGB branch that can define an irr::ext:: library for any extension
diff: @@ -29,6 +29,8 @@ none of which would be optimal for all circumstances such as shadows or deferred
  4) If compiling as a library, it must support out-of-source-build and a static library target.
  5) Do not expose (via public headers) or install your dependencies! (Unless @devsh grants an exceptional waiver)
  +@manhnt9 provided a nice CMake script for setting up an ext library cleanly https://github.com/buildaworldnet/IrrlichtBAW/pull/291#issuecomment-494223131
  +
  ## Rules for exposed dependencies (if @devsh grants a waiver):
  1) This is only for big complicated framework integrations such as CEGUI, PhysX, Bullet, etc. where writing a non-dependency-API-exposing extension would entail a lot of work, pointless wrapper code, and hinder the usability of the underlying dependency.
  