Renaming a role should cause onceover to fail but it does not

[jessereynolds]

Steps to reproduce:

• have onceover spec tests passing for a role, eg "role::base_linux"
• you decide to rename that class, to eg "role::generic_linux"
• you do not update spec/onceover.yaml so it's still testing the old class name
• you onceover run spec again

expected result:

• error along the lines of "no such class found" for role::base_linux

actual result:

• tests pass

workaround:

• rm -rf .onceover && onceover run spec

analysis:

• I guess that the control-repo cache under .onceover is not having files deleted as it should when you run the tests

[jessereynolds]

Related to #95

[dylanratcliffe]

While this is definitely a bug as proven by the failing test, I can't think of a good way to solve it that wouldn't massively affect the performance. This should be fixable once we have moved to r10k deploy from r10k puppetfile