Rework modules to be individual objects rather than references to templates

src/app/shipyard/Modification.js

@@ -0,0 +1,15 @@
+/**
+ * Modification - a modification and its value
+ */
+export default class Modification {
+
+  /**
+   * @param {String} id         Unique modification ID
+   * @param {Number} value      Value of the modification
+   */
+  constructor(id, value) {
+    this.id = id;
+    this.value = value;
+  }
+
+}