Fix namespace issues in libgnt and finch.
's/ENTRY_CHAR/GNT_ENTRY_CHAR/g'
's/g_hash_table_duplicate/gnt_hash_table_duplicate/g'
's/GDupFunc/GntDuplicateFunc/g'
's/gnt_append_menu_action/finch_append_menu_action/g'
's/gnt_ui_init/finch_ui_init/g'
's/gnt_ui_uninit/finch_ui_uninit/g'