Merge branch 'tb/utf-16-le-with-explicit-bom'

A new encoding UTF-16LE-BOM has been invented to force encoding to
UTF-16 with BOM in little endian byte order, which cannot be directly
generated by using iconv.

* tb/utf-16-le-with-explicit-bom:
  Support working-tree-encoding "UTF-16LE-BOM"

compat/precompose_utf8.c

@@ -79,7 +79,7 @@ void precompose_argv(int argc, const char **argv)
 		size_t namelen;
 		oldarg = argv[i];
 		if (has_non_ascii(oldarg, (size_t)-1, &namelen)) {
-			newarg = reencode_string_iconv(oldarg, namelen, ic_precompose, NULL);
+			newarg = reencode_string_iconv(oldarg, namelen, ic_precompose, 0, NULL);
 			if (newarg)
 				argv[i] = newarg;
 		}