fortran: enable ptype/whatis for modules.

fortran: enable ptype/whatis for modules.

Added new domain MODULE_DOMAIN for fortran modules to avoid
issues with sharing namespaces (e.g. when a variable currently
in scope has the same name as a module).

	(gdb) ptype modname
	old> No symbol "modname" in current context.
	new> type = module modname

This fixes PR 15209 and also addresses the issue
with sharing namespaces:
https://sourceware.org/ml/gdb-patches/2013-02/msg00643.html

2013-11-19  Keven Boell  <keven.boell@intel.com>
            Sanimir Agovic  <sanimir.agovic@intel.com>

	* cp-namespace.c (cp_lookup_nested_symbol): Enable
	nested lookups for fortran modules.
	* dwarf2read.c (read_module): Add fortran module to
	the symbol table.
	(add_partial_symbol, add_partial_module): Add fortran
	module to the partial symbol table.
	(new_symbol_full): Create full symbol for fortran module.
	* f-exp.y (yylex): Add new module domain to be parsed.
	* symtab.h: New domain for fortran modules.

testsuite/

	* gdb.fortran/module.exp: Completion matches fortran module
	names as well. ptype/whatis on modules return a proper type.
	Add new check for having the correct scope.