The unary modulus operation does not require extra parentheses to be
printed in cases like “|X + Y|”. This adds a new option to the printing
routine to omit parentheses in cases where the parent expression already
defines a parenthesis-like scope (currently only with unary operations).
Because of a bug in the Clingo API, the exponentation operator was not
properly exposed to anthem. This updates Clingo to a version with a
fixed API and adds proper support for exponentation within anthem along
with a matching unit test.