[test suite] extended code structure errstr test to validate perl FKO constants
[perl FKO module] bug fix for missing error code constants (caught with code structure test)
[test suite] extended code structure errstr test to validate python extention error code constants
[python extension] bug fix for missing error code constants (caught with code structure test)
added tests/code_structure.pl file to Makefile.am
[test suite] remove init file before starting test run