bump nsync
bump nsync

[finishes #114967203]

Submodule src/github.com/cloudfoundry-incubator/nsync 5ea94c1..7902bea:
  > buildpack recipebuilder test fixup to reflect actual behavior
  > test cleanup on recipebuilder
  > explicitly label channels in processor construction
  > task differ construction and diff method matches app differ

Signed-off-by: Utako Ueda <c5738b62d376b6008768780d19980e9b499f1bae@pivotal.io>

cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release