Update build.gradle

Updated gradle version, compileSdkVersion with the corresponding buildToolsVersion. Using implementation instead of compile as of gradle 3.0.1.

Author: mahomahoxd

android/build.gradle

@@ -1,8 +1,8 @@
 apply plugin: 'com.android.library'
 
 android {
-    compileSdkVersion 25
-    buildToolsVersion "25.0.3"
+    compileSdkVersion 27
+    buildToolsVersion "27.0.3"
 
     defaultConfig {
         minSdkVersion 16
@@ -19,8 +19,8 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libs', include: ['*.jar'])
-    testCompile 'junit:junit:4.12'
-    compile 'com.android.support:appcompat-v7:23.4.0'
-    compile "com.facebook.react:react-native:+"  // From node_modules
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    testImplementation 'junit:junit:4.12'
+    implementation 'com.android.support:appcompat-v7:27.0.2'
+    implementation "com.facebook.react:react-native:+"  // From node_modules
 }