This release adds data type support for complex numbers, allows to
close iterations and adds first support for backend configuration
options (via JSON), which are currently implemented for ADIOS2.
Further installation options have been added (homebrew and CLI tool
support with pip). New free standing functions and macro defines are
provided for version checks.

Thanks to Axel Huebl, Franz Poeschel, and Lígia Diana Amorim for
contributing to this release!