Top level patterns change broke testsuite

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Hi, it appears #99 (Handle top-level patterns a bit easier) broke testcase 9.hs. A cursory look still leaves me confused as to why it broke, but I assume it's because of the changed logic in re disambiguating tuples and top-level operators?

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In fact, checking at the REPL, I have no idea why #99 was accepted -- it breaks parsing in so many ways.
Testing with

dumpNames bs =
    let FileData _ things = findThingsInBS "" bs
    in [name | FoundThing _ name _ <- things]

I have:

ghci> dumpNames "a = b"
["a"]
ghci> dumpNames "(a,b) = (c,d)"
["a","c(=)b",")d"]
ghci> dumpNames "(a\n ,b) = (c,d)"
["a","c(=)b",")d"]
ghci> dumpNames "(a\n,b) = (c,d)"
*** Exception: src/Hasktags.hs:576:3-51: Non-exhaustive patterns in (pre, _ : post)
ghci> dumpNames "(a,b,c) = undefined"
["a","b","undefined=)c"]

These are clearly incorrect, and I'm actually surprised this situation isn't exercised -- the two only cases remotely approximating testing this are 9.hs and typesig.hs

Also, testing dumpbNames "a,b,c :: Int", I'm surprised to see the names appear reversed -- why is this done?