Use logging in modelica system syntron (#228)

* [ModelicaSystem] raise IOError if files are missing

* [ModelicaSystem] define verbose as a class variables

* this simplifies a lot of functions!

* [ModelicaSystem] add class ModelicaSystemError and use it

* class variable _raiseerrors
* functions _check_error() & _raise_error()

* [ModelicaSystem] use _check_error()

* [ModelicaSystem] use _raise_error()

* [ModelicaSystem] use 'raise ModelicaSystemError'

* [ModelicaSystem] convert remaining print() to log messages using logger.*()

* [ModelicaSystem] fix comment

* [ModelicaSystem] use function setCommandLineOptions()

* [ModelicaSystem] raise error if loadLibrary() fails

* [ModelicaSystem] fix default argument - PyCharm: default argument value is mutable

* [PyCharm:ModelicaSystem] style cleanup

* [ModelicaSystem] add missing check for self-_verbose in loadFile()

Author: syntron