Changed routing framework from mux to Gin.

Swagger doc is now included in the application.
A fronted can now be hosted from the application.

.idea/MusicServer.iml

@@ -1,6 +1,14 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <module version="4">
-  <component name="Go" enabled="true" />
+  <component name="Go" enabled="true">
+    <buildTags>
+      <option name="customFlags">
+        <array>
+          <option value="prod" />
+        </array>
+      </option>
+    </buildTags>
+  </component>
   <component name="NewModuleRootManager">
     <content url="file://$MODULE_DIR$" />
     <orderEntry type="sourceFolder" forTests="false" />