[Fix #1512] Fix false negative for typical string formatting examples

Using args instead of *args in unpacking the :send node was a
bug that meant we counted the child nodes of the first argument
to determine number of arguments for format/sprintf.
Merge pull request #1517 from jonas054/kakutani/fix-false-negative-format-string

[Fix #1512] Fix false negative for typical string formatting examples
Remove disallowed array syntax in specs
Merge pull request #1519 from bquorning/remove-disallowed-array-syntax

Remove disallowed array syntax in specs
Extract method .load_yaml_configuration
Fail with TypeError if config file is malformed