gui: Avoid using HAVE_QSCINTILLA in more header files. * gui-settings.h, settings-dialog.h: Don't include QScintilla header. Forward-declare QSciLexer class instead if necessary. Declare all member functions unconditionally. * gui-settings.cc (gui_settings::get_valid_lexer_styles, gui_settings::read_lexer_settings), settings-dialog.cc (settings_dialog::update_lexer, settings_dialog::get_lexer_settings, settings_dialog::write_lexer_settings): Define functions unconditionally. * gui-preferences-ed.h: Don't include QScintilla header. Remove definition of local variable os_eol_mode from header. * gui-preferences-ed.cc (os_eol_mode): Move definition of local variable here.

EXTERNAL_SOURCES += \
  %reldir%/datv.f \
  %reldir%/dcnst0.f \
  %reldir%/dcnstr.f \
  %reldir%/ddasic.f \
  %reldir%/ddasid.f \
  %reldir%/ddasik.f \
  %reldir%/ddaspk.f \
  %reldir%/ddstp.f \
  %reldir%/ddwnrm.f \
  %reldir%/dfnrmd.f \
  %reldir%/dfnrmk.f \
  %reldir%/dhels.f \
  %reldir%/dheqr.f \
  %reldir%/dinvwt.f \
  %reldir%/dlinsd.f \
  %reldir%/dlinsk.f \
  %reldir%/dmatd.f \
  %reldir%/dnedd.f \
  %reldir%/dnedk.f \
  %reldir%/dnsd.f \
  %reldir%/dnsid.f \
  %reldir%/dnsik.f \
  %reldir%/dnsk.f \
  %reldir%/dorth.f \
  %reldir%/dslvd.f \
  %reldir%/dslvk.f \
  %reldir%/dspigm.f \
  %reldir%/dyypnw.f