Closes #47

Patch adds command line options and configuration file support to unreliablefs. unreliablefs can be managed in runtime using simple .INI configuration file. unreliablefs config uses configuration language which provides a structure similar to what's found in Microsoft Windows INI files or used by configparser Python module [2]. To make it possible third-party C library [1] has been imported. There is only one supported error injection - "errinj_noop" that replaces file operation with no operation. More error injections are coming. 1. https://github.com/benhoyt/inih 2. https://docs.python.org/3/library/configparser.html Closes #3 Closes #18 Closes #1 Closes #7 Closes #12 Closes #60