Don't add pandoc-citeproc filter if natbib or biblatex is used

See https://github.com/jgm/pandoc-templates/issues/42
Fixed stupid copy&paste error

How could this happend? sry
Removed code that forces MathJax to typeset.

Closes #1012.  Reopens #966.  A better solution for #966 will just
affect slideous, not the other slide writers.
Setup.hs: Better way of handling man page building.

Previously we tried to remove make-pandoc-man-pages from the list
of packages to be haddocked, installed, copied, etc.

It works better to set 'Buildable: False' on make-pandoc-man-pages,
then have the buildHook temporarily set Buildable to True.  This
allows make-pandoc-man-pages to be built (and used in generating
the man pages), but not installed.
Revert "Setup.hs: Better way of handling man page building."

This reverts commit ed061b91c8e3247e1d3b1538eca24687adf0e575.
LaTeX reader: Fixed character escaping in \url{}.

Previously `\~` wasn't handled properly, among others.
RST writer:  Skip spaces after display math.

Otherwise we get indentation problems, and part of the next
paragraph may be rendered as part of the math.
LaTeX reader:  Ensure that preamble doesn't contribute to text of doc.
HTML writer:  Insert command to typeset mathjax for slideous output.

Closes #966.
Treat div with class "notes" as speaker notes in slide formats.

Currently beamer goes to `\note{}`, revealjs to `<aside class="notes">`,
and the notes are simply suppressed in other formats.

Closes #925.
Require pandoc-types 1.12.3.

This will enforce a certain JSON encoding.
Use isURI instead of isAbsoluteURI.

It allows fragments identifiers.
LaTeX writer:  Add link anchors for code blocks with identifiers.

Closes #1025.
PDF: Minor code cleanup.
LaTeX writer:  Specially escape non-ascii characters in labels.

Otherwise we can get compile errors and other bugs when
compiled with pdflatex.  Closes #1007.

Thanks to begemotv2718 for the fix.
MediaWiki reader: Trim contents of `<math>` tags.

Otherwise we get problems when converting to markdown.

Closes #1027.
Version bump to 1.12.0.3.
Updated changelog.
Fixed '. . .' (pause) on HTML slide formats.  Closes #1029.

The old version caused a pause to be inserted before the first
material on a slide. This has been fixed.
Pass the buildDir as first argument to test suite.

Allows test suite to work with cabal sandboxes.
Previously we hard-coded the build directory.