Fix bug: breakpoints don't work with NA constants such as NA_character_
Fix bug: Shiny breakpoints don't track editor line changes correctly
Fix bug: clicking on the line number itself shouldn't set a breakpoint
Fix bug: when debugging inside a fold, fold doesn't open automatically
Merge remote-tracking branch 'origin/master' into bugs/breakpoints
Show full deparsed function call and frame number for the traceback.
Fix bug: debugger can get invoked at the top level in some contexts
Merge pull request #73 from rstudio/bugs/breakpoints

Fix user-reported annoyances in debugging features