dynamicLogWithPP does not support Unicode properly!! It was encoding
each "Char" (32 bits in Haskell, mind you!) to a utf-8 byte instead of a
codepoint. The result was a butchared faux-utf8 encoded string.

This was causing xmobar to crash with unicode + my truncating code. I
have now moved away from dynamicLogWithPP and am writing my own log
string manually. It's better this way anyway; less hacky; more
fine-grained control.

It wasn't working as expected for flips. This is because the
avoidStructs layout modifier was too low in the layout stack.

i.e. would rather show 'My Title' rather than 'My Titl ...'

This is done by removing all visible characters after a certain point. Right now
that's set to 70, which was found just via trial-and-error.

This will break if something has '>' or '<' and this will not be able to handle
xmobar's 'raw' tag, but it's good enough.