Change extended filenames logic
Change extended filenames logic

Change the logic to determine valid characters in extended filenames to
a whitelist. Unicode characters in filenames were causing file system
errors in Linux.

skiingwiz/sagetv,jfthibert/sagetv,OpenSageTV/sagetv,webernissle/sagetv,jlverhagen/sagetv,andyvshr/sagetv,gasinger/sagetv,jusjoken/sagetv,JREkiwi/sagetv,JREkiwi/sagetv,enternoescape/sagetv,jason-bean/sagetv,gasinger/sagetv,BartokW/sagetv,OpenSageTV/sagetv,JustFred51/sagetv,stuckless/sagetv,skiingwiz/sagetv,jusjoken/sagetv,andyvshr/sagetv,enternoescape/sagetv,webernissle/sagetv,BartokW/sagetv,JustFred51/sagetv,jusjoken/sagetv,OpenSageTV/sagetv,google/sagetv,OpenSageTV/sagetv,atarijeff/sagetv,gasinger/sagetv,jlverhagen/sagetv,skiingwiz/sagetv,stuckless/sagetv,atarijeff/sagetv,google/sagetv,stuckless/sagetv,webernissle/sagetv,enternoescape/sagetv,jfthibert/sagetv,andyvshr/sagetv,jlverhagen/sagetv,jusjoken/sagetv,BartokW/sagetv,jason-bean/sagetv,JREkiwi/sagetv,jfthibert/sagetv,jason-bean/sagetv,jason-bean/sagetv,atarijeff/sagetv,atarijeff/sagetv,tmiranda1962/sagetv-1,stuckless/sagetv,tmiranda1962/sagetv-1,webernissle/sagetv,google/sagetv,tmiranda1962/sagetv-1,google/sagetv,skiingwiz/sagetv,JREkiwi/sagetv,BartokW/sagetv,jfthibert/sagetv,andyvshr/sagetv,enternoescape/sagetv,JustFred51/sagetv,tmiranda1962/sagetv-1,gasinger/sagetv,jlverhagen/sagetv,JustFred51/sagetv