Merge branch 'maint'

* maint:
  Let check_preimage() use memset() to initialize "struct checkout"
  fetch/push: fix usage strings

builtin/push.c

@@ -10,7 +10,7 @@
 #include "parse-options.h"
 
 static const char * const push_usage[] = {
-	"git push [<options>] [<repository> <refspec>...]",
+	"git push [<options>] [<repository> [<refspec>...]]",
 	NULL,
 };