show template list in new R Markdown dialog
show option list for each format (disconnected)
create option UI appropriate to option type
compose YAML front matter on server; include non-default options
improve New RMarkdown dialog layout; add more options
add support for floating-point R Markdown format options
add a subset of presentation format options
add support for format-specific R Markdown option variants
add R Markdown format definition for Word
Merge remote-tracking branch 'origin/master' into feature/new-rmarkdown-dialog

Conflicts:
	src/cpp/session/modules/SessionRMarkdown.R
	src/gwt/src/org/rstudio/studio/client/rmarkdown/model/RMarkdownServerOperations.java
	src/gwt/src/org/rstudio/studio/client/workbench/views/source/editors/text/TextEditingTargetRMarkdownHelper.java
Merge pull request #93 from rstudio/feature/new-rmarkdown-dialog

New R Markdown dialog
fix R Markdown render output display on Linux desktop
add alternate help link for rmarkdown extended type
use desktop showFile for rmarkdown pdf preview
UI tweaks for New R Markdown dialog
use file extensions to determine previewer type
Merge branch 'master' of github.com:/rstudio/rstudio
showPDF method
implement showPDF using sumatra on windows
update format options for presentation formats