work in progress fixing let
Merge branch 'master' of github.com:JuliaLang/julia into jb/let
finish up new let implementation
Merge branch 'master' of github.com:JuliaLang/julia into jb/let
Merge branch 'master' of github.com:JuliaLang/julia into jb/let
update documentation for 'let'
Merge branch 'master' of github.com:JuliaLang/julia