Add prettier

.prettierignore

@@ -0,0 +1 @@
+require.build.js

.prettierrc

@@ -0,0 +1,3 @@
+semi: false
+singleQuote: true
+useTabs: true

package.json

@@ -3,6 +3,7 @@
     "@babel/cli": "^7.0.0",
     "@babel/core": "^7.0.0",
     "@babel/preset-env": "^7.0.0",
+    "prettier": "^2.1.2",
     "requirejs": "^2.3.6",
     "terser": "^4.6.7"
   }

yarn.lock

@@ -1812,6 +1812,11 @@ posix-character-classes@^0.1.0:
   resolved "https://registry.yarnpkg.com/posix-character-classes/-/posix-character-classes-0.1.1.tgz#01eac0fe3b5af71a2a6c02feabb8c1fef7e00eab"
   integrity sha1-AerA/jta9xoqbAL+q7jB/vfgDqs=
 
+prettier@^2.1.2:
+  version "2.1.2"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-2.1.2.tgz#3050700dae2e4c8b67c4c3f666cdb8af405e1ce5"
+  integrity sha512-16c7K+x4qVlJg9rEbXl7HEGmQyZlG4R9AgP+oHKRMsMsuk8s+ATStlf1NpDqyBI1HpVyfjLOeMhH2LvuNvV5Vg==
+
 process-nextick-args@~2.0.0:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/process-nextick-args/-/process-nextick-args-2.0.1.tgz#7820d9b16120cc55ca9ae7792680ae7dba6d7fe2"