exp/template: simplify method and function calls by using the value's Method rather than the type's, so a method's invocation works the same as a function's.
exp/template: simplify method and function calls by using the value's Method
rather than the type's, so a method's invocation works the same as a function's.

R=golang-dev, rsc, r
CC=golang-dev
http://codereview.appspot.com/4704049

sanjosh/sanjos100-tipc,glycerine/jeaten-go-arrayof-structof,mhennings/marcohennings-go,Triskite/willstone-goclone,mhennings/marcohennings-go,webfd/go-zh,rflanagan/reginaldflanagan-project1,sanjosh/sanjos100-tipc,sanjosh/sanjos100-tipc,mhennings/marcohennings-go,bryanxu/go-zh,bryanxu/go-zh,rdp/rogerpack2005-golang,scirelli/scirelli-go,npe9/noahevans-go9,webfd/go-zh,sanjosh/sanjos100-tipc,d0f/go-zh,Triskite/willstone-goclone,Triskite/willstone-goclone,glycerine/jeaten-go-arrayof-structof,rdp/rogerpack2005-golang,Triskite/willstone-goclone,scirelli/scirelli-go,npe9/noahevans-go9,glycerine/jeaten-go-arrayof-structof,sanjosh/sanjos100-tipc,webfd/go-zh,webfd/go-zh,rdp/rogerpack2005-golang,rflanagan/reginaldflanagan-project1,glycerine/jeaten-go-arrayof-structof,Triskite/willstone-goclone,npe9/noahevans-go9,mhennings/marcohennings-go,bryanxu/go-zh,npe9/noahevans-go9,mhennings/marcohennings-go,d0f/go-zh,rflanagan/reginaldflanagan-project1,rflanagan/reginaldflanagan-project1,d0f/go-zh,d0f/go-zh,d0f/go-zh,scirelli/scirelli-go,scirelli/scirelli-go,mhennings/marcohennings-go,bryanxu/go-zh,sanjosh/sanjos100-tipc,npe9/noahevans-go9,rflanagan/reginaldflanagan-project1,mhennings/marcohennings-go,rdp/rogerpack2005-golang,webfd/go-zh,rflanagan/reginaldflanagan-project1,scirelli/scirelli-go,sanjosh/sanjos100-tipc,bryanxu/go-zh,npe9/noahevans-go9,bryanxu/go-zh,glycerine/jeaten-go-arrayof-structof,rflanagan/reginaldflanagan-project1,mhennings/marcohennings-go,glycerine/jeaten-go-arrayof-structof,Triskite/willstone-goclone,webfd/go-zh,Triskite/willstone-goclone,scirelli/scirelli-go,npe9/noahevans-go9,npe9/noahevans-go9,bryanxu/go-zh,glycerine/jeaten-go-arrayof-structof,bryanxu/go-zh,d0f/go-zh,scirelli/scirelli-go,sanjosh/sanjos100-tipc,rdp/rogerpack2005-golang,rdp/rogerpack2005-golang,webfd/go-zh,scirelli/scirelli-go,rdp/rogerpack2005-golang,glycerine/jeaten-go-arrayof-structof,d0f/go-zh,d0f/go-zh,webfd/go-zh,Triskite/willstone-goclone,rflanagan/reginaldflanagan-project1,rdp/rogerpack2005-golang