pkg-export-k8s: Make Manifest fields public
pkg-export-k8s: Make Manifest fields public

There is no reason for them to be private and we'll soon need to access
them in the upcoming Helm exporter.

Signed-off-by: Zeeshan Ali <f7a8e49325fe4a238df42df4f7e30abcfdad87c6@kinvolk.io>

rsertelon/habitat,habitat-sh/habitat,habitat-sh/habitat,nathenharvey/habitat,habitat-sh/habitat,nathenharvey/habitat,georgemarshall/habitat,habitat-sh/habitat,habitat-sh/habitat,georgemarshall/habitat,georgemarshall/habitat,rsertelon/habitat,rsertelon/habitat,georgemarshall/habitat,georgemarshall/habitat,georgemarshall/habitat,nathenharvey/habitat,georgemarshall/habitat,habitat-sh/habitat,rsertelon/habitat,rsertelon/habitat,nathenharvey/habitat,habitat-sh/habitat,nathenharvey/habitat,rsertelon/habitat,nathenharvey/habitat,georgemarshall/habitat,habitat-sh/habitat,rsertelon/habitat