LaTeX/Beamer templates:  Add classoption variable.

This is intended for class options like `oneside`; it may
be repeated with different options.
LaTeX template:  Added `biblio-style` variable.
default.beamer: Add font theme option

Add font theme option to choose one of the sets of structural fonts
that come predefined with Beamer.
Merge pull request #36 from logc/master

default.beamer: Add font theme option
opendocument template: fixed office:version.
Adds meta tag to allow scaling by the user.  This makes things friendlier for smaller screen sizes.
Merge pull request #38 from ErikEvenson/pr/html5-meta-scale

Adds meta tag to allow scaling by the user.
default.opendocument: Add $font-face-decls$ field.
Merge pull request #41 from wilx/master

default.opendocument: Add $font-face-decls$ field.
opendocument: Replaced fontface variable with actual declaration.
Beamer template:  put slide around bibliography with natbib or biblatex.
Beamer template: Consistent styles for figure and table captions
ConTeXt template:  setup captions with no numbering.

See pandoc #1067.
ConTeXt template:  Setup up defaults for floats.

This allows the user to adjust the figure and table placement
and numbering globally.
LaTeX template: Add booktabs package
Merge pull request #47 from jlduran/booktabs

LaTeX template: Add booktabs package
Beamer template: add booktabs package
Merge pull request #48 from lionandoil/master

Beamer template: add booktabs package
Added abstract variable in latex template.
latex template:  Put header includes after title.

Closes pandoc#908.