feat(interface): add interface for the message builder

Author: sciborrudnicki

src/message-builder/interface/message-template.interface.ts

@@ -0,0 +1,3 @@
+export interface MessageTemplate {
+  [index: string]: string;
+}

src/message-builder/interface/parameter.interface.ts

@@ -0,0 +1,4 @@
+export interface Parameter {
+  name: string;
+  type: string;
+}