Bugfix: issue #80 (#81)
Bugfix: issue #80 (#81)

Bugfix: issue #80 

* Avoid ctor ambiguity by using parentheses for copy ctor invocation with `nlohmann::json` class.
eth-cscs/nestmc-proto,halfflat/nestmc-proto,halfflat/arbor,halfflat/nestmc-proto,halfflat/arbor,halfflat/arbor,eth-cscs/nestmc-proto,eth-cscs/nestmc-proto,halfflat/arbor,halfflat/nestmc-proto,halfflat/arbor