Add S3 Source support for Service Catalog Pipelines

[greghoggard]

Currently S3 is not supported as a source for Service Catalog products. Adding S3 as the Source Provider does not provide the ability to specify the Bucket to pull from. When using S3 as the Source, instead of parsing the repo to get the Source Bucket and Bucket Object and adding those as parameters, it simply retains the Repo and Source Branch parameter fields.