move prettier config to its own file

.editorconfig

@@ -0,0 +1,5 @@
+[*]
+indent_style = tab
+indent_size = 2
+charset = "utf-8"
+trim_trailing_whitespace = true

.prettierrc

@@ -0,0 +1,15 @@
+{
+	"lineWidth": 100,
+	"parser": "flow",
+	"singleQuote": true,
+	"useTabs": true,
+	"semi": true,
+	"trailingComma": "es5",
+	"jsxBracketSameLine": true,
+  "overrides": [
+    {
+      "files": ".prettierrc",
+      "options": { "parser": "json" }
+    }
+  ]
+}

package.json

@@ -43,9 +43,5 @@
 	},
 	"jest": {
 		"preset": "react-native"
-	},
-	"prettier": {
-		"lineWidth": 100,
-		"parser": "flow"
 	}
 }