chore(TypeScript): refactor objects into classes

fix: `Nil`(null, undefined) now renders as empty string
change: `parser.parseValue()` renamed to `parser.parseOutput`
change: registered tags/filters become static and shared across different liquid instances

src/render/render.ts

@@ -0,0 +1,24 @@
+import { stringify, create } from 'src/util/underscore'
+import { RenderBreakError, RenderError } from 'src/util/error'
+import assert from 'src/util/assert'
+import Scope from 'src/scope/scope'
+
+export default class Render {
+  async renderTemplates (templates, scope) {
+    assert(scope, 'unable to evalTemplates: scope undefined')
+
+    let html = ''
+    for (const tpl of templates) {
+      try {
+        html += await tpl.render(scope)
+      } catch (e) {
+        if (e instanceof RenderBreakError) {
+          e.resolvedHTML = html
+          throw e
+        }
+        throw e instanceof RenderError ? e : new RenderError(e, tpl)
+      }
+    }
+    return html
+  }
+}