use member prefs
call base onApply from editing preferences
updated R completion icons
updated function icon
update to pandoc 1.13.1 (on all platforms save for RHEL5)
update NEWS
change pandoc version to 1.13.1 on windows
check that completion from cache is not null in 'usingCache'
Merge pull request #199 from rstudio/bugfix/completion-cache-exception

check that completion from cache is not null in 'usingCache'
return empty completions rather than NULL
ensure 'methods' is actually loaded first
use .rs.normalizePath
eliminate 'mustWork' argument (unnecessary)
don't try an roxygen completion until an '@' has been inserted
Merge pull request #200 from rstudio/bugfix/completion-exceptions

Other completion exceptions + small fixes
merge with master