($(outdir)/%.pdf): add DVIPS_FLAGS. This will

($(outdir)/%.pdf): add DVIPS_FLAGS. This will
create scalable PS and PDFs  for input/{test,template,regression}.

* lily/context.cc (is_alias): move function.
	(is_alias): add Bottom as context alias.
	(find_create_translator): add Bottom as a context alias for creation.

	* lily/stencil.cc: rename Molecule to Stencil. Changes throughout.

	* lily/parser.yy (music_property_def): new syntax for property
	assignments:

	\set A.B = #C , \unset A.B
	\override A.B #C = #D, \revert A.B #C

	* lily/my-lily-lexer.cc: remove \property