Requirement: Make sure all dependencies exist on Chocolatey.org

[gep13]

This really stems from this package:

https://chocolatey.org/packages/Internode_Monthly_Usage_Meter/8.6.3

Which has a dependency on SampleDependency, which is a package that doesn't exist. We either need to check explicitly for that dependency name, or we need to go further and check that a package with that name actually exists.

[ferventcoder]

Also created #90.

[ferventcoder]

This one may get tricky - need to validate against submitted as well.