feat: enable onload callbacks (#414)

* refactor(examples): run ssr example from server

* chore: switch to babel for build

buble complains too much

* feat: enable loaded callbacks

feat: add skip option

* examples: add async-callback browser example

* examples: fix server

* examples(ssr): add reactive script with callback

* fix: also skip on ssr

* chore: remove unused var

* feat: only add mutationobserver if DOM is still loading

feat: disconnect mutation observer once DOM has loaded

* examples: pass vmid to loadCallback instead of el

* feat: also support load callbacks for link/style tags

* test: add unit tests for load

* test: add load e2e test

* chore: fix lint

* chore: remove unused files

* test: fix e2e load callback test

* test: fix attempt

* examples: ie9 compatiblity

destructuring doesnt work in ie9

* fix: add onload attribute on ssr

dont rely on mutationobserver

* chore: lint ci conf

* refactor: remove loadCallbackAttribute config option

test: fix coverage for load

* test: improve coverage

* fix: only use console when it exists (for ie9)

* chore: fix coverage

package.json

@@ -82,6 +82,7 @@
     "browserstack-local": "^1.4.0",
     "chromedriver": "^75.1.0",
     "codecov": "^3.5.0",
+    "copy-webpack-plugin": "^5.0.3",
     "eslint": "^6.0.1",
     "eslint-config-standard": "^13.0.1",
     "eslint-plugin-import": "^2.18.0",
@@ -93,6 +94,7 @@
     "esm": "^3.2.25",
     "fs-extra": "^8.1.0",
     "geckodriver": "^1.16.2",
+    "get-port": "^5.0.0",
     "is-wsl": "^2.1.0",
     "jest": "^24.8.0",
     "jest-environment-jsdom": "^24.8.0",
@@ -103,7 +105,7 @@
     "puppeteer-core": "^1.18.1",
     "rimraf": "^2.6.3",
     "rollup": "^1.17.0",
-    "rollup-plugin-buble": "^0.19.8",
+    "rollup-plugin-babel": "^4.3.3",
     "rollup-plugin-commonjs": "^10.0.1",
     "rollup-plugin-json": "^4.0.0",
     "rollup-plugin-node-resolve": "^5.2.0",