Add ktx

ktx/external/fmt/.gitrepo

@@ -0,0 +1,12 @@
+; DO NOT EDIT (unless you know what you are doing)
+;
+; This subdirectory is a git "subrepo", and this file is maintained by the
+; git-subrepo command. See https://github.com/ingydotnet/git-subrepo#readme
+;
+[subrepo]
+	remote = https://github.com/fmtlib/fmt.git
+	branch = 2dd4fa8742fdac36468f8d8ea3e06e78215551f8
+	commit = 40626af88bd7df9a5fb80be7b25ac85b122d6c21
+	parent = 443e122381d2cc9e4ee608ef0b0d2e7bbbbf9a22
+	method = merge
+	cmdver = 0.4.9