Merge branch 'jl/doc-submodule-update-checkout'

Add missing documentation for "submodule update --checkout". * jl/doc-submodule-update-checkout: submodule update: consistently document the '--checkout' option

Junio C Hamano committed Mar 14, 2014 at 14:26 UTC d73e6160031e1753c81cf0d72b0f9525cf93dca0

No changes.