Improve lattice-bundle error message
Improve lattice-bundle error message

[Finishes #102909512]

Signed-off-by: Colin Jackson <4f4efc23f45cfd2ccaeb623d4ab84100edb791f6@pivotal.io>

datachand/lattice,datachand/lattice,cloudfoundry-incubator/ltc,cloudfoundry-incubator/ltc,felipeg48/lattice,davidwadden/lattice,davidwadden/lattice-release,datachand/lattice,SrinivasChilveri/lattice,datachand/lattice,SrinivasChilveri/lattice,Klaudit/lattice,davidwadden/lattice,felipeg48/lattice,Klaudit/lattice,svrc-pivotal/lattice,Klaudit/lattice,SrinivasChilveri/lattice,svrc-pivotal/lattice,davidwadden/lattice-release,Klaudit/lattice,svrc-pivotal/lattice,SrinivasChilveri/lattice,svrc-pivotal/lattice