fetch object content on demand for large objects
show progress UI while fetching object contents from the server
fix improperly scaled breakpoint icon
Merge pull request #66 from rstudio/bugfix/deferred-contents

Enable expansion of large objects in environment list view
add iostream include to http/header
allow error inspector to attach to any error emitted since the last command was issued from the console
Merge branch 'v0.98-shiny' of github.com:rstudio/rstudio into v0.98-shiny
Merge branch 'v0.98-shiny' into feature/shiny-debugging-improvements

Conflicts:
	src/gwt/src/org/rstudio/studio/client/workbench/views/environment/EnvironmentPane.java
	src/gwt/src/org/rstudio/studio/client/workbench/views/environment/view/EnvironmentObjectDisplay.java
	src/gwt/src/org/rstudio/studio/client/workbench/views/environment/view/EnvironmentObjectsObserver.java