[Update] deprecate `*_by_column_and_row*` methods

[john-dc252]

Changes:

• deprecate *_by_column_and_row* methods
• deprecate index_from_coordinate_simple
• add struct CellCoordinates for cell coordinates
• make methods that take address strings as parameters generic and accept Into<CellCoordinates> instead

The changes listed above will allow having just one method/function for things that need an address string or column and row index. This means methods like get_cell do not need a separate get_cell_by_column_and_row anymore. e.g.

// both these calls are now valid
worksheet.get_cell("C2");
worksheet.get_cell((3, 2));

[MathNya]

Wow, thanks for the cool suggestion. I will merge them.