Update to latest support library + SDK version (KeepSafe#257)

Was pretty outdated previously.

app/build.gradle

@@ -1,13 +1,13 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 25
-    buildToolsVersion "25.0.2"
+    compileSdkVersion 27
+    buildToolsVersion "27.0.2"
 
     defaultConfig {
         applicationId "com.getkeepsafe.taptargetviewsample"
         minSdkVersion 14
-        targetSdkVersion 25
+        targetSdkVersion 27
         versionCode 1
         versionName "1.0"
     }
@@ -20,8 +20,8 @@ android {
 }
 
 dependencies {
-    compile project(':taptargetview')
-    compile 'com.android.support:appcompat-v7:25.1.1'
-    compile 'com.android.support:design:25.1.1'
-    compile 'com.facebook.stetho:stetho:1.5.0'
+    implementation project(':taptargetview')
+    implementation 'com.android.support:appcompat-v7:27.0.2'
+    implementation 'com.android.support:design:27.0.2'
+    implementation 'com.facebook.stetho:stetho:1.5.0'
 }

build.gradle

@@ -13,6 +13,7 @@ buildscript {
 allprojects {
     repositories {
         jcenter()
+        google()
     }
 }
 

taptargetview/build.gradle

@@ -8,18 +8,18 @@ version = '1.11.0'
 description = 'An implementation of tap targets from the Material Design guidelines for feature discovery'
 
 android {
-    compileSdkVersion 25
+    compileSdkVersion 27
 
     defaultConfig {
         minSdkVersion 14
     }
 }
 
-def supportLibraryVersion = '25.3.0'
+def supportLibraryVersion = '27.0.2'
 dependencies {
-    compile "com.android.support:support-annotations:$supportLibraryVersion"
-    compile "com.android.support:support-compat:$supportLibraryVersion"
-    compile "com.android.support:appcompat-v7:$supportLibraryVersion"
+    implementation "com.android.support:support-annotations:$supportLibraryVersion"
+    implementation "com.android.support:support-compat:$supportLibraryVersion"
+    implementation "com.android.support:appcompat-v7:$supportLibraryVersion"
 }
 
 install {