maint: remove trailing empty lines.

* cfg.mk: No longer skip sc_prohibit_empty_lines_at_EOF, except
	for parse-gram.h (generated).
	* examples/mfcalc/.gitignore, lib/.gitignore, m4/.gitignore,
	* po/.gitignore, runtime-po/.gitignore: Remove trailing/leading
	empty lines.

Conflicts:

	examples/mfcalc/.gitignore

po/.gitignore

@@ -1,4 +1,3 @@
-
 /*.gmo
 /*.po
 /*.po~
@@ -21,4 +20,3 @@
 /remove-potcdate.sed
 /remove-potcdate.sin
 /stamp-po
-