- Changing from static methods to public methods
- Adding dev-composer-dependency Mockery for static method mocking (f.e. Config, DBA)
- Adding ModeTest with Mocking
- removing bootstrap from phpunit.xml because of double loading tests\bootstrap.php

Extracted install business functions to new Class `Install.php`

- Move executed code to separate readStdin function

Issue #3878

Issue #3878

- max_proccesses_reach() and maxload_reached() (why no _ behind max?) are called
  both way, static and with object reference.
- this is strongly discouraged and should be avoided as its support (in PHP) may
  be dropped in future releases.
- used $a = get_app(); to encapsulate code (even when the function does
  currently the same, it may be changed later)

Signed-off-by: Roland Häder <roland@mxchange.org>