License was changed from GPLv3 to AGPLv3. This is because the main benefits of GPLv3 are felt for binary distributions. However, this library is intended to be used for server-side applications which are typically not distributed. AGPLv3 extends GPLv3's definition of "distribution" to include uses over networks such as the Internet, and thus extends the terms of GPLv3 to usage over the internet.
There were no internal library changes.