like it's defined in GIOFuncs for glib2
moved src/fe-text/utf8.* to src/fe-common/core
changed get_utf8_char so it returns a status code and the unichar argument pointer
to the value that it returned before if there were no errors,
so you can check for a negative value an handle the error
git-svn-id: http://svn.irssi.org/repos/irssi/trunk@4091 dbcabf3a-b0e7-0310-adc4-f8d773084564