Project structure refactor:

- Change package name general_server to gateway
- Changing the structure of directories and packages
- Adding vendor to the project

vendor/github.com/spf13/viper/.yamllint.yaml

@@ -0,0 +1,6 @@
+ignore-from-file: [.gitignore, .yamlignore]
+
+extends: default
+
+rules:
+  line-length: disable