Unogenerator

- Improved test coverage to 81%
- pydicts module is now used for list of dictionaries methods
- Added new methods to add values without styles. They are used to edit styled templates files. New methods: addCell, addCellMerged, addRow, addColumn, addListOfRows, addListOfColumns

- Improved get_values speed

- Optimize addRowWithStyle addColumnWithStyle and addListOfRowsWithStyle.
- Removed cellbycell parameter from this methods.

- Added ODT method to insert a HTML block

- Fixed bug deleting default sheet
- Migrated to poetry installation method

- Added method is_server_working()