fix(bcmethod): make bcmethod abstract

lib/src/test/java/net/tomatentum/cutin/TestBestCandidateMethod.java

@@ -0,0 +1,28 @@
+package net.tomatentum.cutin;
+
+import net.tomatentum.cutin.method.BestCandidateMethod;
+
+public class TestBestCandidateMethod extends BestCandidateMethod<String, Double> {
+
+    protected TestBestCandidateMethod(String methodName, Object containingObject) {
+        super(methodName, containingObject);
+    }
+
+    @Override
+    public Object getParameter(Double context, int index) {
+        switch (index) {
+            case 0:
+                return context;
+            case 1:
+                return "testString";
+            default:
+                return null;
+        }
+    }
+
+    @Override
+    public String identifier() {
+        return "ident";
+    }
+    
+}