consider filtering production data to only those companies we have an ID and/or ISIN for

[cjyetman]

Our current production data is quite large and likely contains a lot of data about private companies and or other companies that we will not be able to match to a company/entity ID nor to any ISIN. It would be advantageous to remove such companies from the prepared dataset to reduce the size and complexity. This would likely be done in new_data_prep.R in the section where ABCD data is being prepared for output here.