Take language from Outlook instead of the system
* src/oomhelp.cpp (invoke_oom_method_with_parms_type): New. Helper to allow invokes with a custom type. (invoke_oom_method_with_parms): Use it. (get_ol_ui_language): New. Read out the UI language of outlook. * src/w32-gettext.c (_nl_locale_name): Use it. * src/oomhelp.h: Update accordingly.
It makes sense to use the same language as outlook does. Users
will find anything else confusing and broken.
This also makes it easier to switch languages for screenshots :-P