Major refactoring

proto/hook.proto

@@ -0,0 +1,27 @@
+syntax = "proto3";
+
+package hooks.v1;
+
+option go_package = "/v1";
+
+service HookService {
+  rpc ExecuteHook(ExecuteHookRequest) returns (ExecuteHookResponse);
+}
+
+message Hook {
+  string name = 1;
+  repeated string command = 2;
+  string user = 3;
+  string group = 4;
+  string cwd = 5;
+  int32 timeout_seconds = 6;
+  map<string, string> env = 7;
+}
+
+message ExecuteHookRequest {
+  Hook hook = 1;
+}
+
+message ExecuteHookResponse {
+  string error = 1;
+}