Use webpack to build files and webpack-dev-server for testing (#1068)

* Create a separate entry point for webpack

Created a webpack entry point for KaTeX, which imports katex.less. As
flow[1] and jest[2] doesn't support CSS modules natively, a separate
entry point is used and it is not flowtyped.

[1] https://gist.github.com/lambdahands/d19e0da96285b749f0ef
[2] https://facebook.github.io/jest/docs/en/webpack.html

* Use webpack to build files

* Made webpack.config.js export valid webpack configuration
* Use:
browserify -> webpack
babelify -> babel-loader
UglifyJS CLI -> UglifyJsPlugin
Less CLI -> less-loader
cleancss -> cssnano in css-loader
build/fonts -> file-loader
* Inline CSS(Less) using style-loader and export them using
ExtractTextPlugin
* Add `watch` npm script calling `webpack --watch`

* Improve local testing(webpack-dev-server)

* Made webpackDevServer export a valid webpack configuration
* Compile Less and inline CSS using less-loader and style-loader
* Instead of copying files serve files from /static and use file-loader
* Remove old server.js and its dependencies

* Use webpack-dev-server in Screenshotter

* Include contrib in webpack-dev-server

+ Moved common configurations to webpack.common.js

* Rename webpackDevServer.js to webpack.dev...

to be consistent, avoid confusion with webpack-dev-server and follow
webpack configuration naming convention.

* Remove unnecessary conditional output.path

* Use map instead of reduce

+ Add comments regarding function arguments

* Remove unnecessary mkdir and clean build/* before build

* Use katex as external dependency instead of global variable in contrib

Fixes #692.

* Unblock codes as they are built as a module

* Update package-lock.json

* Add comments regarding devServer option

* Lint renamed webpack.dev.js

a0d8b33

* Export ES6 module and expose its default export

* Revert "Browserify hotfix (#1057)"

This reverts commit f6b509123b.

* Enables colors on the console when running the dev server in Screenshotter

* Add context to webpack configuration

Allows webpack to be run from other directories

* Move `rm -rf build/*` to npm scripts

* Check dependencies before build

* Move UglifyJsPlugin into config creation

* Let webpack handle ES6 modules

Do not transform modules to commonjs in Babel. However Jest doesn't not
support ES6 modules, so transfrom modules to commonjs when NODE_ENV is
`test`.

* Add documentation on testing in IE 9 and 10 using webpack-dev-server

Changed version range to include IE-compatible version

package.json

@@ -3,7 +3,6 @@
   "version": "0.10.0-pre",
   "description": "Fast math typesetting for the web.",
   "main": "dist/katex.js",
-  "browser": "dist/katex.min.js",
   "repository": {
     "type": "git",
     "url": "git://github.com/Khan/KaTeX.git"
@@ -25,23 +24,20 @@
     "babel-preset-es2015": "^6.18.0",
     "babel-preset-flow": "^6.23.0",
     "babel-register": "^6.26.0",
-    "babelify": "^7.3.0",
-    "browserify": "^13.3.0",
     "check-dependencies": "^1.1.0",
-    "clean-css": "^3.4.23",
+    "css-loader": "^0.28.8",
     "eslint": "^4.14.0",
     "eslint-plugin-flowtype": "^2.40.1",
-    "express": "^4.14.0",
+    "extract-text-webpack-plugin": "^3.0.2",
+    "file-loader": "^1.1.6",
     "flow-bin": "^0.62.0",
-    "glob": "^7.1.1",
     "jest": "^22.0.4",
     "jest-serializer-html": "^4.0.1",
     "js-yaml": "^3.3.1",
     "json-stable-stringify": "^1.0.1",
     "jspngopt": "^0.2.0",
     "less": "~2.7.1",
-    "less-plugin-clean-css": "^1.5.1",
-    "morgan": "^1.7.0",
+    "less-loader": "^4.0.5",
     "nomnom": "^1.8.1",
     "object-assign": "^4.1.0",
     "pako": "1.0.4",
@@ -49,26 +45,26 @@
     "rimraf": "^2.6.2",
     "selenium-webdriver": "^2.48.2",
     "sri-toolbox": "^0.2.0",
+    "style-loader": "^0.19.1",
     "stylelint": "^8.4.0",
     "stylelint-config-standard": "^18.0.0",
-    "uglify-js": "~2.7.5",
+    "uglifyjs-webpack-plugin": "^1.1.6",
     "webpack": "^3.6.0",
-    "webpack-dev-server": "^2.8.2"
+    "webpack-dev-server": "^2.7.1"
   },
   "bin": "cli.js",
   "scripts": {
-    "lint": "eslint katex.js server.js cli.js webpack.config.js webpackDevServer.js src test contrib dockers && stylelint static/fonts.less static/katex.less",
+    "lint": "eslint katex.js katex.webpack.js cli.js webpack.common.js webpack.config.js webpack.dev.js src test contrib dockers && stylelint static/fonts.less static/katex.less",
     "flow": "flow",
     "jest": "jest",
     "jest-update": "jest --updateSnapshot",
     "coverage": "jest --coverage",
-    "copy": "cp -a static/. build/ && cp -a contrib build/",
     "clean": "rm -rf build/* node_modules/",
     "clean-install": "npm run clean && npm i",
     "test": "check-dependencies && npm run lint && npm run flow && npm run jest",
-    "build-css": "lessc --clean-css static/katex.less build/katex.css",
-    "prestart": "rimraf build && npm run build-css && npm run copy",
-    "start": "check-dependencies && node webpackDevServer.js",
+    "start": "check-dependencies && webpack-dev-server --open --config webpack.dev.js",
+    "build": "check-dependencies && rimraf build/* && webpack",
+    "watch": "npm run build -- --watch",
     "prepublishOnly": "make NIS= dist"
   },
   "pre-commit": [