Major rewrite of how ld is configured. The major idea

	Major rewrite of how ld is configured.  The major idea
	is to use shell scripts to generate everything.
	* generic.em replaces ldtemplate.
	* Other *.em files replace various *.c files.
	A *.em file is a shell script that generates the corresponding
	ld__*.c file that implements an emulation.  This is usually
	a straight 'cat' of a here-document, possibly with substitutions.
	* Script files (*.sc) are places by *.sc-sh scripts.
	Again, these are simple shell scripts that 'cat'
	here-documents, usually with some substitutions.
	The output a *.sc-sh is a script file.