Merge pull request rust-lang#79 from allanlw/addr-leak-not-unsafe

Clarify that address leaks aren't considered unsafe

Author: steveklabnik

src/behavior-not-considered-unsafe.md

@@ -7,6 +7,7 @@ or erroneous.
 ##### Deadlocks
 ##### Leaks of memory and other resources
 ##### Exiting without calling destructors
+##### Exposing randomized base addresses through pointer leaks
 ##### Integer overflow
 
 If a program contains arithmetic overflow, the programmer has made an