Improved configs system

– Now config of bemy is named .bemy.json.
– Now bemy will try to find .bemy.json on the every previous level (like npm) until the root directory, so you can put .bemy.json into your home directory or project directory if you need different options depend on project. Otherwise bemy will take .bemy.json from own directory.
– Option output renemed to debug.
– Added --debug key.
– now bemy open existing file if there is -o key (bemy isn't rewriting existing files)