rmd output preview: edit slide command
Merge branch 'master' of github.com:/rstudio/rstudio
set preview_slide to -1 by default
close word document prior to rendering on Windows
put presentation slide information in correct JSON object
preserve expansion for large data frames when updated in environment pane
remove subtitle and attributes from slide title
remove unused components from NOTICE
check for null before forwarding satellite reactivation params
set preview anchor correctly for slides reactivation
tighten polling interval for rmd preview navigation
remove redundant focus call
don't call get_init_messages in desktop mode
infrastructure to retrieve and apply document position on reload

TODO:
* use specific doc opened (ActiveDocument could return a different doc)
* bind position to the document name
operate on Word document last viewed
add find text box to RmdOutputPanel
use legacy rendering if rstudio.markdownToHTML
raise glass over rmd preview when menu is active
restore scroll position on load for HTML documents
launch new Word process when old one is closed