implement next session project function
stub in rEnvironmentForNextSession function
Revert "stub in rEnvironmentForNextSession function"

This reverts commit f5dbfde93d8addb222738bc9f5e9a5cf333601b7.
move RVersionInfo structure to it's own header file
get the r version for the next session
introduce RVersionNumber for version comparisons
implement selectVersion function
add setREnvironmentVars that takes an Options collection
add command to save source files and refresh viewer
Revert "highlighting for chain operator"

This reverts commit 844c76be109a74bb3751a06b0295aa8916db7363.
Use new htmltools API for dependencies
add htmltools dependency for rmarkdown
add ptrace to startup profile
Fix small typo

Reviewed by @jmcphers
Index more file types (.py, .sh, .sql, .Rprofile)
Also find 'configure', 'cleanup', 'Makevars' files
Fix bug in register for filenames w/no extension
Merge pull request #109 from rstudio/feature/new-file-types

Index more file types (.py, .sh, .sql, .Rprofile)
update knitr dependency to 1.6
don't log path not found error for missing library