Reactivated the 'Coloring' page in struct array cell_format_pages.
* src/dialog-cell-format.c: Reactivated the 'Coloring' page in struct array cell_format_pages. * src/dialog-cell-format.c (create_coloring_page): Lots of changes, practically a full rewrite. One problem is that cells are thrown into this world with the flag STYLE_FORE_COLOR of their style set, which causes a lack of synchronization with what is expressed in the global variable foreground_radio_list. * src/dialog-cell-format.c (apply_coloring_format): By the moment being, deactivated the call of function cell_set_pattern, along with the STYLE_PATTERN bit flag of style->valid_flags. I will concentrate in fg/bg coloring of the cell.