Add cfs fcbf #39 (#40)

* Implement CFS/FCBF in splitter

* Split Splitter class to its own file
Update hyperparams table in docs
Implement CFS/FCBS with max_features and variable type

* Set mfs to continuous variables

* Fix some tests and style issues in Splitter

* Update requirements in github CI

setup.py

@@ -44,7 +44,7 @@ setuptools.setup(
         "Topic :: Scientific/Engineering :: Artificial Intelligence",
         "Intended Audience :: Science/Research",
     ],
-    install_requires=["scikit-learn", "numpy"],
+    install_requires=["scikit-learn", "numpy", "mfs"],
     test_suite="stree.tests",
     zip_safe=False,
 )