update .babelrc, .gitignore, and others

.babelrc

@@ -1,4 +1,20 @@
 {
-  "presets": ["es2015", "stage-2"],
-  "plugins": ["transform-flow-strip-types"]
+  "plugins": [
+    "transform-class-properties",
+    "transform-object-rest-spread",
+    "transform-react-jsx",
+    ["transform-runtime", {
+      "polyfill": false,
+      "regenerator": true
+    }]
+  ],
+  "presets": [
+    ["env", {
+      "targets": {
+        "browsers": ["last 2 versions", "ie >= 9", "safari >= 7"]
+      },
+      "modules": "commonjs",
+      "loose": true
+    }]
+  ]
 }

.flowconfig

@@ -1,10 +0,0 @@
-[ignore]
-
-[include]
-./src
-
-[libs]
-
-[options]
-module.name_mapper.extension='less' -> '<PROJECT_ROOT>/src/flow/LessModule.js'
-suppress_comment=\\(.\\|\n\\)*\\$FlowFixMe

.gitignore

@@ -1,9 +1,25 @@
-.idea
-.vscode
-dist
-lib
-downloads
-node_modules
-flow-typed
-*.zip
-npm-debug.log
+# See https://help.github.com/ignore-files/ for more about ignoring files.
+
+# dependencies
+/node_modules
+
+# testing
+/coverage
+
+# production
+/build
+/lib
+/dist
+
+# misc
+.DS_Store
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+.idea   # webstorm
+.vscode # visual studio code
+
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*