update gitignore

.gitignore

@@ -1,8 +1,52 @@
+# Built application files
+*.apk
+*.ap_
+
+# Files for the ART/Dalvik VM
+*.dex
+
+# Java class files
+*.class
+
+# Generated files
+bin/
+gen/
+out/
+
+# Gradle files
+.gradle/
+build/
+
+
+# Built application files
+/*/build/
+
+
+# Local configuration file (sdk path, etc)
+local.properties
+
+# Proguard folder generated by Eclipse
+proguard/
+
+# Log Files
+*.log
+
+# Android Studio Navigation editor temp files
+.navigation/
+
+# Android Studio captures folder
+captures/
+
+# Intellij
 *.iml
-.gradle
-/local.properties
-/.idea/workspace.xml
-/.idea/libraries
 .DS_Store
-/build
 /captures
+
+# Keystore files
+*.jks
+
+# External native build folder generated in Android Studio 2.2 and later
+.externalNativeBuild
+
+.idea/
+app/build/