added doc header
translated README to markdown + small changes
2014
allow multiple parameters to be passed to the constructor
fix retrieving errors from the thread

because isRunning() will return false if there are 
errors in the thread, we were never getting into 
the function that tried to retrieve errors
fix typo to properly pass varargs
don't hang the loader if it's never given any resources to load

previously, if there were never any resources passed to the loader 
resourceBeingLoaded wouldn't be set and pending would never have 
anything in it so the thread would never terminate

this implementation requires a final update call after all resources 
have been loaded