[S02] clarify that Pairs and Mappings are mutable in value, but not in key
[S02] clarify that Pairs and Mappings are mutable in value, but not in key


git-svn-id: 53605643c415f7495558be95614cf14171f1db78@24819 c213334d-75ef-0310-aa23-eaa082d1ae64

perl6/specs,prammer/specs,prammer/specs,prammer/specs,tokuhirom/specs,tokuhirom/specs,tokuhirom/specs,perl6/specs