Started working in 2.0.0

* removed 1.x code
* worker pools
* locking
* unit tests
started implementing config
work in progress on downloader.js
cleanup
added download test
enabled downloads to be streamed again.
added item key to locks
renamed "download" module
fixed config loading with no additional paths
added childprocess module
renaming in source module
download test with config parameter
added analyzer + test
Added converter + tests
minor changes to fix concurrency issues
reimplemented centered and "aoi covergage" cropping
implemented new cropping modes. refs #30
utility for checking freshness of responses. refs #44
new cache system
simpler format strings instead of mime types