Java/Cfg: Introduce new shared CFG library and replace the Java CFG.

java/ql/consistency-queries/CfgConsistency.ql

@@ -0,0 +1,2 @@
+import java
+import ControlFlow::Consistency

java/ql/lib/printCfg.ql

@@ -21,7 +21,7 @@ external int selectedSourceColumn();
 
 private predicate selectedSourceColumnAlias = selectedSourceColumn/0;
 
-module ViewCfgQueryInput implements ViewCfgQueryInputSig<File> {
+module ViewCfgQueryInput implements ControlFlow::ViewCfgQueryInputSig<File> {
   predicate selectedSourceFile = selectedSourceFileAlias/0;
 
   predicate selectedSourceLine = selectedSourceLineAlias/0;
@@ -42,4 +42,4 @@ module ViewCfgQueryInput implements ViewCfgQueryInputSig<File> {
   }
 }
 
-import ViewCfgQuery<File, ViewCfgQueryInput>
+import ControlFlow::ViewCfgQuery<File, ViewCfgQueryInput>