Remove all TODOs from the test suite

[masak]

Current crop:

$ git grep -w TODO t
t/01-fn-read.t:!TODO: currently the printer doesn't handle "special" symbols
t/comfns.t:> "TODO (< \\a \\c) ==> t"
t/comfns.t:"TODO (< \\a \\c) ==> t"
t/comfns.t:> "TODO (< \\d \\b) ==> nil"
t/comfns.t:"TODO (< \\d \\b) ==> nil"
t/comfns.t:> "TODO (< \"aa\" \"ac\") ==> t"
t/comfns.t:"TODO (< \"aa\" \"ac\") ==> t"
t/comfns.t:> "TODO (< \"bc\" \"ab\") ==> nil"
t/comfns.t:"TODO (< \"bc\" \"ab\") ==> nil"
t/comfns.t:> "TODO (< 'aa 'ac) ==> t"
t/comfns.t:"TODO (< 'aa 'ac) ==> t"
t/comfns.t:> "TODO (< 'bc 'ab) ==> nil"
t/comfns.t:"TODO (< 'bc 'ab) ==> nil"
t/example-bel.t:> "TODO: (dedup:sort < \"abracadabra\") ==> \"abcdr\""
t/example-bel.t:"TODO: (dedup:sort < \"abracadabra\") ==> \"abcdr\""
t/fn-rdex.t:!TODO: currently the printer doesn't handle "special" symbols
t/mac-record.t:!TODO: The `pr` function does not yet respect `outs`

After fixing these TODOs, we could also remove the !TODO directive from L::B::Test::DSL.

[masak]

Seems we're down to three TODOs.

t/fn-rdex.t:!TODO: currently the printer doesn't handle "special" symbols
t/fn-read.t:!TODO: currently the printer doesn't handle "special" symbols
t/mac-record.t:!TODO: The `pr` function does not yet respect `outs`

These correspond to #266 and #253.

加油!