Attune getScriptsAndArgs() function:
1) Python script passed as a parameter to runSalome not necessarily has .py extension; for instance SALOME non-regression grid includes scripts without extension (A0, A1, A2, etc...).
2) Python scripts passed as a parameter to runSalome can have execution permission but not specify execution interpreter (Python) in the header; so we have to explicitly call python <script> in this case (this is the case for unitary tests in GEOM, SMESH and probably other modules).
