Add math limit component (#2510)

src/file/paragraph/math/n-ary/math-limit.ts

@@ -0,0 +1,13 @@
+// http://www.datypic.com/sc/ooxml/e-m_lim-1.html
+import { XmlComponent } from "@file/xml-components";
+import { MathComponent } from "../math-component";
+
+export class MathLimit extends XmlComponent {
+    public constructor(children: readonly MathComponent[]) {
+        super("m:lim");
+
+        for (const child of children) {
+            this.root.push(child);
+        }
+    }
+}