GLib will automatically convert command line options to UTF-8 provided that setlocale(LC_TYPE, "") is called first, and the argument type is STRING (but not FILENAME). Update the CLI tools to take advantage of this behavior, and likewise implement it in fakeglib.
GLib does not automatically convert non-option arguments (i.e. everything remaining in argv after option processing), so manually call g_locale_to_utf8 on these arguments when they represent table names. This should fix the CLI tools when processing non-ASCII table names in non-UTF-8 locales. Also update fakeglib to implement a fast and loose version of g_locale_to_utf8, and factor out some of the code page => iconv name logic in iconv.c so it can be used in our fake g_locale_to_utf8. This adds a new symbol mdb_iconv_name_from_code_page that is not advertised in the main header file. I did not want to include mdbtools.h from fakeglib.c, but maybe that's not important.
* Migrate the Windows Msys2 build from Appveyor to GitHub Actions
* Fix build with newer versions of Msys2 (fix `vasprintf` conflict)
* Enable SQL tests on the Cygwin build on Appveyor
* Fix an error message about Bison not being available when in fact Flex was not available
* Don't fail fast with Mac and Linux GitHub Actions
