* scm/parser-ly-from-scheme.scm: rename from ly-from-scheme.scm

* scm/parser-ly-from-scheme.scm: rename from ly-from-scheme.scm

* scm/parser-clef.scm (supported-clefs): rename from clef.scm

* scm/layout-slur.scm: rename from slur.scm

* scm/layout-page-layout.scm: rename from page-layout.scm

* scm/layout-beam.scm: rename from beam.scm

* scm/define-grob-interfaces.scm (bass-figure-interface): add
bass-figure-interface

* lily/new-figured-bass-engraver.cc (process_music): add
implicitBassFigures property.

* scm/define-markup-commands.scm (pad-x): new markup.

* ly/engraver-init.ly (AncientRemoveEmptyStaffContext): set
minimumVerticalExtent on FiguredBass context.

* lily/figured-bass-continuation.cc (center_on_figures): kludge in
case the continuation crosses a line break.