wire in completions for reference classes
don't preview keypress when not in R mode
Merge pull request #222 from rstudio/feature/check-r-mode

don't let R completion manager preview keypress when not in R mode
Merge pull request #221 from rstudio/feature/completions-reference-classes

wire in completions for reference classes
stricter check re: presence of .DollarNames method
don't rely on 'getAnywhere' -- too much chance of false positive
avoid loading package namespaces when getting help
fix bug: tab bar doesn't scroll to fill empty space on the right
Merge branch 'master' into feature/r-completion-signature-tooltip

Conflicts:
	src/gwt/src/org/rstudio/studio/client/workbench/views/console/shell/assist/RCompletionManager.java