StackStudio should support AWS VPC Route Tables

[huxoll]

Currently, StackStudio doesn't show route table operations for VPC.

[bears4barrett]

Need support in fog: fog/fog#1720

[rbclark]

Fog now supports aws route tables.

[huxoll]

Pushing this to backlog; still need it, nobody's working it presently.

[lvalerio]

Update: You are now able to display, create and delete route tables in StackStudio. Adding routes, associating subnets and propagating routes are left to be implemented.