* pan/otp_8683_compiler_warnings:
  Remove (harmless) warning regarding auto-imported BIF max/2
  Update primary bootstrap
  Correct warnings and errors for auto-imported bif clashes

Conflicts:
	bootstrap/lib/stdlib/ebin/erl_lint.beam

Change erl_lint not to recognize this type as builtin and
add a new erl_lint.beam version in bootstrap.

Add an -opaque type declaration for this type in ets.erl
and also declare this as an exported type. Use this type
in file debugger/src/dbg_iload.erl in a spec.
While at it, also clean up this later file a bit.

erl_lint has been updated so that it takes the new -export_type()
attribute into account.
This means:
 - do not complain about types which are defined but nowhere used in the
   module but exported to other modules
 - check that all types which are exported are indeed defined in the module
 - warn when there are multiple occurrences of exported types.

In doing this change, I've also taken the liberty to introduce many types and
specs for functions of this module and to do small cleanups here and there.