* src/Makefile.am: Fix windres call to include config.h
* src/addin-options.cpp (enable_disable_opts): Enable buttons
 depending on mime_ui.
 (options_window_proc): Add handling for mime_ui checkbox.
* src/common.h (struct opts): Add mime_ui option.
* src/dialogs.h (IDC_ENABLE_SMIME): Define.
* src/dialogs.rc: Add checkbox for mime_ui.
* src/gpgoladdin.cpp: Switch ui code depending on opt.mime_ui.
* src/main.c (read_options, write_options): Handle mime_ui.
* src/mapihelp.cpp (get_msgcls_from_pgp_lines): Handle mime_ui.