add option to disable print on stdout for unselected cases from select file

[Bhavyeshkumars]

As i have started using pytest-select plugin, it is printing the non-selected cases onto console by default.
Let say i have 1000 test cases and i am trying to run multiple pytest command which will have set of test cases instead of all test cases and i want to maintain only one file for complete test suite.
It is making log huge and difficult to do analyses. We need to disable printing the unselected cases.
Could you add option to disable print on stdout for unselected cases from select file ?
https://github.com/ulope/pytest-select/blob/master/pytest_select/plugin.py#L100