Fixed not writing specs to directory

[iamwilhelm]

The code had problems at every stage:

Fetching stage

During fetching, it wasn't writing anything to the directory, because it was trying to write a keymap to file, instead of a string.

Also, the key for the spec listings in the discovery file changed from url to discoveryRestUrl.

I changed the with statements to case, just so I could get it working, and I understood it. Uglier, but it works.

Conversion stage

Similar problem as fetching, but it wasn't writing, because the directory openapi had never been created

Build stage

Just had to state what the current docker image should be.

However, had a question here...once I generated the client, it had all these new empty files that were generated. Is that suppose to happen?

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[chingor13]

Thanks for the PR!

For fetching, the 404s will go away when I remove the APIs that should not be there.

For converting, we should ensure that the openapi directory exists, or create it. (Created #12)

For generating the client, you are getting empty files and not the latest generated code as we are using the fork from the pending PR to swagger-codegen (so it's not in the master image).