Explain why 	-flag true does not work although 	-flag=true does.
Explain why
	-flag true
does not work although
	-flag=true
does.

Fixes issue 139.

R=iant
CC=golang-dev
http://codereview.appspot.com/154118

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