Update example docs and assets to reflect new directory upload schema

[salsferrazza]

Example docs no longer accurately reflect the directory upload scheme to follow for ingestion. Assets should be renamed and example specimens adjusted so that they may be used in place without revision.

[ramfordt]

https://github.com/GoogleCloudPlatform/bq-datashare-toolkit/tree/master/examples/mlb failed at this step "cd bq-datashare-toolkit/ingestion/function"