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/sourcegraph/conc/.golangci.yml

@@ -0,0 +1,11 @@
+linters:
+  disable-all: true
+  enable:
+    - errcheck
+    - godot
+    - gosimple
+    - govet
+    - ineffassign
+    - staticcheck
+    - typecheck
+    - unused