npm install lodash --save-dev
make stringifyException a property of sendUncaughtException, return closure in exceptionalException
require lodash (script tag)
add tests: verify stringify exception doens't eliminate Error's message property, verify exceptionalException returns timer id (type number)
export sendUncaughtException as AMD module, exceptionalException is always added to the window object
misc. docs (incl. for sendUncaughtException.stringifyException)