Clarify data connection language & options

Users are experiencing confusion when connecting non-database data sources (Google sheets and CSVs).

Problems
1. Connecting a Google Sheet is located in the "Connect database" option. Users do not think of Google Sheets as a database and do not go there to intuitively connect a GSheet.

2. "Upload CSV" is presented in the main data menu, which makes users think uploading a CSV is an easy data connection option. However, CSVs cannot be uploaded without a database present, which is confusing to users.

Need to change language/menu options around data upload to make this less confusing for users.