updated for version 7.3.070

Problem:    Can set environment variables in the sandbox, could be abused.
Solution:   Disallow it.

src/eval.c

@@ -2326,7 +2326,7 @@ ex_let_one(arg, tv, copy, endchars, op)
 	    else if (endchars != NULL
 			     && vim_strchr(endchars, *skipwhite(arg)) == NULL)
 		EMSG(_(e_letunexp));
-	    else
+	    else if (!check_secure())
 	    {
 		c1 = name[len];
 		name[len] = NUL;

src/version.c

@@ -714,6 +714,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    70,
 /**/
     69,
 /**/