MediaWiki reader: Accept image links in more languages

In some of the Wikipedia versions the local version of 'File' is used (for example 'Archivo' in Spanish)
PDF: Use / as path separators in latex input only

Fixes compile error on Windows for 5040f3e
Reverted back to canonical file separators </> in all places except for
arguments to the LaTeX builder and in TEXINPUTS

See #1151.

Note: Temporary directories still fail to be removed in Windows due to
call of ByteString.Lazy.readFile creating process ownership of the
compiled pdf file.
Merge pull request #1190 from eVITAERC/patch/1151-windows-texlive

PDF: Use / as path separators in latex input only
Man writer:  Ensure that terms in definition lists aren't line wrapped.

Closes #1195.
RST writer:  Avoid stack overflow with certain tables.

Closes #1197.

Note that there are still problems with the formatting of
the tables inside tables with output produced from the input
file in the original bug report.  But this fixes the stack
overflow problem.
EPUB writer:  Incorporate files linked in <video> tags.

src and poster will both be incorporated into content.opf
and the epub container.

This partially address #1170.
Still need to do something similar for <audio>.
EPUB writer:  Handle media in audio source tags.

This should resolve the rest of #1170, but it needs
extensive testing.

Note that we now use a 'media' directory rather than 'images'.
EPUB writer:  Handle files linked in raw img tags.

See #1170.
Remove Makefile.
PDF:  Changes to error reporting, to handle non-UTF8 error output.
beamer template:  changes for better unicode handling.

Ported from LaTeX template.  Thanks to KarolS for the patch.
Markdown reader: Fixed regression on line breaks in strict mode.

Closes #1203.
Fixed typo in README
Parsing:  Make F an instance of Applicative.  Closes #1138.
Merge pull request #1068 from jaimeMF/mw-images-langs

MediaWiki reader: Accept image links in more languages
RTF writer:  Fixed tables cells containing paragraphs.

This moves \intbl after \pard.
LaTeX reader:  Better handling of "table" environment.

Positioning options no longer rendered verbatim.
Partially addresses #1204.
API changes to HasReaderOptions, HasHeaderMap, HasIdentifierList.

Previously these were typeclasses of monads.  They've been changed
to be typeclasses of states.  This ismplifies the instance definitions
and provides more flexibility.

This is an API change!  However, it should be backwards compatible
unless you're defining instances of HasReaderOptions, HasHeaderMap,
or HasIdentifierList.  The old getOption function should work as
before (albeit with a more general type).

The function askReaderOption has been removed.
extractReaderOptions has been added.
getOption has been given a default definition.

In HasHeaderMap, extractHeaderMap and updateHeaderMap have been added.
Default definitions have been given for getHeaderMap, putHeaderMap,
and modifyHeaderMap.

In HasIdentifierList, extractIdentifierList and updateIdentifierList
have been added.  Default definitions have been given for
getIdentifierList, putIdentifierList, and modifyIdentifierList.

The ultimate goal here is to allow different parsers to use their
own, tailored parser states (instead of ParserState) while still
using shared functions.
Whitespace change, and note:

Contrary to the previous commit message, there was no API
change, since Text.Pandoc.Parsing is not an exposed module.
Parsing:  Added HasMacros, simplified other typeclasses.

Removed updateHeaderMap, setHeaderMap, getHeaderMap,
updateIdentifierList, setIdentifierList, getIdentifierList.