Update systematics suffix (#246)
As suggested in #246, update all branches impacted by systematics to all end up with _%SYS%, i.e. no more %SYS% in the middle of the variables.
The default configuration includes a single underscore before %SYS%, but this is configurable through the systematics_suffix_separator argument. As Analysis:bb𝝉𝝉 brought up they would rather use a triple underscore, their base config is already adjusted accordingly.
Edited by Thomas Strebler