add new getter named declaration to use same instance on local module and external module avoiding uncohesion

[pauloantonelli]

with upgrade to 5.0 the exported instances cant be used on origin module anymore, and to use it we need would replicate the same declaration on getter binds.
I propolse do like angular's module and has an declaration getter for local instances or has a export getter to export instances.
But in any case unless bind isn't an factory the instance need to be the same on module getters because the cohesion it's important for the module, and we can have this cohesion with the same instances to same signatures.