Fix typing non-ascii into bpython-urwid (in recent urwids).
Fix typing non-ascii into bpython-urwid (in recent urwids).

Bug reported by mercutio22 on freenode.

aktorion/bpython,aktorion/bpython,wevial/bpython,kdart/bpython,wevial/bpython,kdart/bpython