Summary:
* Allow generate-native-modules-specs-cli.js to generate Android specific files
* Add stub impl for Java spec generation (the output are still incomplete, see the next diffs for missing impl + tests)
* Adjust the CLI to only produce modules stuffs, there's no need to produce components code
Changelog: [Internal]
Reviewed By: mdvacca
Differential Revision: D22860936
fbshipit-source-id: 38aae390189f143f6c6216995437ac1ff15a1788
Kevin Gozali