Maven central publish (#1086)

Summary:
Sets up the plugins necessary to publish to Maven Central.

Pull Request resolved: https://github.com/facebook/yoga/pull/1086

Test Plan: ./gradlew publishToMavenLocal -PRELEASE_SIGNING_ENABLED=false

Reviewed By: mweststrate

Differential Revision: D28604529

Pulled By: passy

fbshipit-source-id: 2c35b94ce0e254bc7a8bc80e449ac5dadb5def38

java/proguard-annotations/build.gradle

@@ -9,3 +9,5 @@ apply plugin: 'java'
 
 sourceCompatibility = '1.7'
 targetCompatibility = '1.7'
+
+apply plugin: 'com.vanniktech.maven.publish'