* src/main.c: Include macrotab.h.

* src/main.c: Include macrotab.h.
* src/macrotab.h (macro_entry_s): Constify fields.
Adjust functions prototypes.
* src/macrotab.c (macro_insert): Constify key and value.
(macro_find): Constify key.
(macro_insert): Include 'xalloc.h'
(macro_insert): Use XMALLOC.
(macro_find): Constify return value.
* src/output.c (output_table_data): Rename table to table_data.
(output_parser): Constify macro_key, macro_value.