deprecate Proc#bind that can cause symbol memory leak

[lest]

https://groups.google.com/forum/#!msg/rubyonrails-core/ucD1rQ2KbpU/mys8W5xHmsUJ

if i run my application for long enough time i start getting errors like this:

RuntimeError: symbol table overflow (symbol __bind_1328993330_18...)

apparently it's because symbols are never GCed and rails generates one every time this proc extension is used because method names are implicitly converted to symbols