This reverts commit c5a2d036d7.
This commit was reverted since it breaks 'go run *.go', I plan on
bringing back custom config.json location with a switch instead.
Instead of looking for config.json form current directory when running the program, look for the config.json from the executable running directory. This will allow for calling fail2rest executable from a service w/o getting the "failed to open config: config.json" error.
