Defective export of turtle-stuff to Java and Python

[codemanyak]

The mechanism to export turtle-controlling algorithms to Java (#441) and Python (#623) is flawed: The intended import clauses are often not generated or not at least in the correct circumstances. This has been due to some misconceptions about the internal order of code export steps. The detection of the existence of turtle-specific contents in diagrams must be reorganised in both cases.

[codemanyak]

Correct logic established, also introduced for C++. ready for version 3.32-36.

The remaining deficiencies could only be solved based on an exact mapping of turtle use to called subroutines or library code.