Suggestions to bhl_inventory/README.md

[MaryseLT]

Here are a few suggestions I have about the BHL inventory instructions:

1. Under bullet points, write out clarification notes. For example:

• sequence_num
  • This is only used when you are utilizing Jackie for batch ripping.

2. It would be helpful to have a few notes or examples for what qualifies a removable media to be separated under the "seperation (Y/N)" bullet point found under the "Transfer" header. https://github.com/hyeeyoungkim/bhl_born_digital_utils/blob/master/bhl_inventory/README.md#transfer