initial work on cpp completion icons (still need new icons)
Merge pull request #196 from rstudio/feature/r-autocompletion-tweaks

Remove function auto-popup; fix errors when trying to get help
register rstudio as an editor for c/c++ files
Merge branch 'master' of github.com:rstudio/rstudio
factor all completion / codesearch icons into CodeIcons class
require devtools v1.4.1 for all devtools oriented features
require roxygen2 v4.0 (enables us to get rid of the roclet configuration UI)
roxygen: default to use rd, collate, and namespace roclets
add stub for file code icon
map r completion types to code icons
updated code icons
add ability to get source document path from r completion manager
Use source index to get completions from current package
only suggest top-level functions
work on source index completions
don't auto-accept on a suggestion after an accepted completion
don't auto-suggest for function arguments
helper for creating named list