Test suite changes for new highlighting-kate version.
Text.Pandoc:  Added readJSON, writeJSON to the API.

Closes #817.
Added `--filter` option.

This makes it easier to use JSON filters.  Instead of
doing

    pandoc -t json | ./filter | pandoc -f json

you can just do

    pandoc --filter ./filter
Revert "Added `--filter` option."

This reverts commit 85dacbb282f34dc45a810d7c7b5a2d639b70e1f5.
Textile reader: Improved handling of `<pre>` blocks.

* Closed #927 (a bug in which `<pre>` in certain contexts was
  not recognized as a code block).
* Remove internal HTML tags in code blocks, rather than printing
  them verbatim.
* Parse attributes on `<pre>` tag for code blocks.
LaTeX reader:  Support `\v{}` for hacek.

Closes #926.
LaTeX writer:  Change `\` to `/` in paths.

`/` works even on Windows in LaTeX.  `\` will cause major problems
if unescaped.
Beamer:  add allowframebreaks to slide if set in header classes.

It's recommended that your bibliography slide have this
attribute:

    # References {.allowframebreaks}

This causes multiple slides to be created if necessary, depending
on the length of the bibliography.
Document that `fancy_lists` turns on `#` as list marker.
Markdown atx headers:  Allow `.` or `)` after `#` if no `fancy_lists`.
Fixed compilation with http-conduit flag False.
Biblio:  Override citeproc-hs's endWithPunct.

The new version correctly sees a sentence ending in '.)' as ending
with punctuation.  This fixes a bug which led such sentences to receive
an extra period at the end: '.).'.  Thanks to Steve Petersen for
reporting.
Biblio:  Don't interfere with Notes that aren't citation notes.

Closes #898: notes not generated from citations were being
adjusted (first letter capitalized, for example, against author's
intentions).
Text.Pandoc.JSON: Use To/FromJSON instances from pandoc-types.

* These use GHC generics rather than syb, and are faster.
* toJsonFilter is now a deprecated synonym of toJSONFilter from
  Text.Pandoc.JSON.
* The deprecated jsonFilter function has been removed.
pandoc.cabal: Removed support for ghc version < 7.2.

There is no point to supporting them, since pandoc-types
requires at least ghc 7.2 for GHC generics.
Text.Pandoc: Don't reexport ToJSONFilter.

It's better just to import this from Text.Pandoc.JSON.
That way, compiled filters will be smaller in size.
MediaWiki writer:  Use native mediawiki tables instead of HTML.

Closes #720.
Removed comment that chokes recent cpp.

Closes #933.
Remove CPP from default-extensions; add pragmas to modules as needed.
Updated changelog.