* add posibility to create a force field that does not have any contributions.
* move to FFConvenience.h and add C++ tests
* deallocate memory
* use range based for loop
Co-authored-by: Greg Landrum <greg.landrum@gmail.com>
* Making adjustments according to the review of @greglandrum
* undo unintentional formatting
* replace TEST_ASSERT with CHECK
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Co-authored-by: Greg Landrum <greg.landrum@gmail.com>
