Merge rnpm cli into react-native

Summary:
This is an initial step of rewriting the CLI interface to use `rnpm` one (commander, plugins etc.).

It's scope is to move all existing commands to use rnpm CLI interface, so that we get plugins, flags and our existing ecosystem working out of the box.

<s>This is still WIP and some of the commands are left commented out.</s>

For the `config` of `rnpm` (functions get info about project and dependency), <s>I am thinking we can merge them with</s> we decided to merge it with [`default.config.js`](e57683e420/local-cli/default.config.js (L33)), so they are available on the `new Config()` [instance](e57683e420/local-cli/cliEntry.js (L59)) (which means we don't have to change anything and current plugins, like runIOS and runAndroid can just start using it [w/o depending on any extra argument](https://github.com/grabbou/react-native/blob/e57683e420210749a5a6b802b4e
Closes https://github.com/facebook/react-native/pull/7899

Differential Revision: D3613193

Pulled By: bestander

fbshipit-source-id: 09a072f3b21e5239dfcd8da88a205bd28dc5d037

local-cli/logAndroid/logAndroid.js

@@ -21,7 +21,7 @@ function logAndroid() {
   });
 }
 
-function _logAndroid(resolve, reject) {
+function _logAndroid() {
   try {
     const adbPath = process.env.ANDROID_HOME
       ? process.env.ANDROID_HOME + '/platform-tools/adb'
@@ -43,9 +43,12 @@ function _logAndroid(resolve, reject) {
     console.log(chalk.red(
       'adb invocation failed. Do you have adb in your PATH?'
     ));
-    reject();
-    return;
+    return Promise.reject();
   }
 }
 
-module.exports = logAndroid;
+module.exports = {
+  name: 'log-android',
+  description: 'starts adb logcat',
+  func: logAndroid,
+};