add a curl_as script for osx
abstract importer streams output always
add file_select text
add file_select text 2
streaming status control and error handling for backend
working import controller for XHR posts
WIP frontent xhr upload client functions
merge ajax and iframe versions of frontend progress bar
catch validation errors that arise before import processing starts
add some pseudo progress output for the xml transformation stage
update batch import spec to reflect change to response format