update compilesdkversion and dependency libraries' version

Author: biodunalfet

app/build.gradle

@@ -1,11 +1,11 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 26
+    compileSdkVersion 27
     defaultConfig {
         applicationId "com.flutterwave.rave_android"
         minSdkVersion 15
-        targetSdkVersion 26
+        targetSdkVersion 27
         versionCode 1
         versionName "1.0"
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
@@ -23,7 +23,7 @@ dependencies {
     androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-    compile 'com.android.support:appcompat-v7:26.1.0'
+    compile 'com.android.support:appcompat-v7:27.0.2'
     compile 'com.android.support.constraint:constraint-layout:1.1.0-beta4'
     testCompile 'junit:junit:4.12'
     compile project(':raveandroid')