Update to 1.4.1. Changes include:

Update to 1.4.1. Changes include:

New intrinsic function: strreplace.
SLang_roll_stack and SLang_reverse_stack functions made public.
SLang_free_function added.
src/slrline.c: Keybindings for ESC O A, etc added.
src/slsmg.c: SLsmg_write_nstring: avoid many loops if an extremely
	large value is passed (> 0x7FFFFFFF).
src/slregexp.c made thread safe
src/slsmg.c: Cursor was not always properly positioned when
	after SLsmg_touch_lines called.
If terminal does not have erase to eol capability, then use spaces.
doc/tm/strops.sl: doc for strcat updated to reflect its ability to
    concatenate N strings.
src/slsmg.c: bug involving SLsmg_set_screen_start fixed.
src/slparse.c: parser was failing to catch misplaced `}'.