Allow passing arguments to runSuiteByInstances

[tp86]

This allows passing multiple arguments to runSuiteByInstances explicitly, without parsing command line. If no arguments are passed, it will still parse command line arguments.

It should ease making test runners that accept (different) arguments on the command line themselves and pass them to runSuiteByInstances.

Currently, runSuiteByInstances accepts commandLineArguments as its second parameter, but it allows only for one value to be passed. If you try to give it more values (like '--exclude', 'something') it will error as only first value is passed to function and command line option is missing value. Passing table of arguments doesn't help either, because initFromArguments accepts multiple values and wraps them in additional table which breaks parsing. To pass different arguments than those provided in command line, you have to modify arg table.