Correct comments in testdir makefiles. (John Beckett)
diff --git a/src/testdir/main.aap b/src/testdir/main.aap
index 5fb93ec..78ef7e0 100644
--- a/src/testdir/main.aap
+++ b/src/testdir/main.aap
@@ -1,5 +1,5 @@
 #
-# Makefile to run al tests for Vim
+# Makefile to run all tests for Vim
 #
 
 VimProg ?= ../vim