Meta-GGA and hybrid xc energy functionals

By efficiently using ADF's fit functions, an initial beta release for a post-SCF implementation of hybrid functionals, such as B3LYP, is available. The first test results show encouraging agreement with literature data and the feasibility of using this option on molecules up to at least 50 atoms. Further improvements and speed-ups are planned. New nonempirical meta-GGA functionals have also been added and often outperform even the most popular hybrid functionals.