Shared: Added function insertMedia which is an alias for M.insert
Added note in README about pipe tables not wrapping in LaTeX/PDF.

See
http://stackoverflow.com/questions/25037357/pandoc-long-tablerows-in-markdown-pdf-documents-do-not-get-linewrap/25050474#25050474
Merge pull request #1472 from mpickering/master

Shared: Added function insertMedia which is an alias for M.insert
Merge branch 'master' of github.com:jgm/pandoc
Made MediaBag a newtype, and added mime type information to media.

Shared now exports functions for interacting with a MediaBag:

- `emptyMediaBag`
- `lookuMedia`
- `insertMedia`
- `mediaDirectory`
- `extractMediaBag`
New module, Text.Pandoc.MediaBag.

Moved `MediaBag` definition and functions from Shared:
`lookupMedia`, `mediaDirectory`, `insertMedia`, `extractMediaBag`.
Removed `emptyMediaBag`; use `mempty` instead, since `MediaBag`
is a Monoid.
pandoc.hs:  Rewrote some of the logic for clarity.
EPUB Reader: Added EPUB reader
Except Compat: Updated to export more module functions
Options: Added option to turn on epub html extensions
HTML Reader: Extended HTML Reader to recognise EPUB specific elements
HTML Reader: Added support for anchors on links and list items
HTML Reader: Added ability to read MathML formatted <math> blocks
EPUB Reader: Integrated into program
EPUB Reader: Added tests
README: Updated with EPUB information
EPUB Reader: Now uses the new MediaBag for images