This PR:
Updates the functionality of setIncrementalStringInput / appendIncrementalStringInput to a more intuitive behavior where append does not replace the current contents of the input.
Adds setStringInput to the API and updates the interactive shell to use this interface.
Updates the examples
Adds new unit tests
This PR adds minor improvements to the SyGuS solver:
Changes the weight of identity rules in the grammar, giving them higher priority during enumeration.
Replaces n-ary operators with their binary version before matching in rcons.
Splits the pattern enumerator for rcons into two enumerators: pattern enumerator and term enumerator.
Adds an option to control geometric distribution parameter used to interleave the 2 enumerators.
Additionally, this PR moves the implementation of the grammar API to an internal class with the Grammar class now a wrapper for the internal class.
I increased cmake's minimum version in order to use the FindPython module, which allows the build system to specify python versions that are supported. Currently the support is extended to 3.6 through 3.10. I also removed some backward compatible conditions that do not apply anymore provided that cmake's minimum version is guaranteed to be 3.12.
MacOS builds are reenabled in ci.yml.
Organizing the PR a bit:
we hook up the subtheories to TheoryFf
we expose FF-related things via the C++/Pytohn API and SMT-LIB2 interface.
we add a bunch of tests against these interfaces.
