[Bornagain-announcements] BornAgain 23 released

This release responds to a change in an external interface: BornAgain 22 requires libcerf 2, BornAgain 23 requires libcerf 3. The roughness model API, which had changed in BornAgain 22, has been corrected to allow again for hurst=0 or correlation_length=0 (resulting in zero scattering). Besides that, some internal cleanup has been done, and the inspection tools plot_int and plot_dif (in directory devtools/view) have been repaired. Python scripts and GUI projects from BornAgain 22 will continue to work. Best greetings from the BornAgain maintainer team: Ammar Nejati, Mikhail Svechnikov, Joachim Wuttke