filter outputs for upload/validation by name

[beckermr]

It appears that when conda build runs downstream tests it leaves the downstream packages in the build artifacts directory. This causes our code to attempt to validate and upload them, which leads to jobs that fail when they should otherwise pass. We can compute the names of the outputs from the meta.yaml (but not their versions) and filter things we find by globing.

Cc @isuruf this is why your binutils pr appears to be failing.

Issue:

Environment (conda list):

``` $ conda list ```

Details about conda and system ( conda info ):

``` $ conda info ```