Locopy

Additional functionality added with some minor clean up and fixes:
- Support for `csv`, `parquet`, and `json` in snowflake copy/unload
- Logging is now dependent on `loguru`
- Bumping up `PyYAML>=5.1` in `requirements.txt`

Major refactoring of code base to allow for extensibility

- **Snowflake support** has now been added
- Upgrade of dependencies (boto3, PyYAML, Sphinx, etc)
- Documentation updates (SQL injection, Snowflake examples)
- General house keeping and cleaning up

Some breaking changes to the API from the previous release. While no new functionality has been added it is more of a refactor to improve future enhancements:

- Splitting up of classes into more distinct units
- `Cmd` and `S3` are now `S3` (for AWS S3 functionality), `Database` for basic DBAPI class interface, and `Redshift` for Load/Unload capabilities which inherits from `S3` and `Database`.
- Clean up of some of the docs, Exceptions, and testing also.

First release to public GitHub!