.gitignore for android

Source: http://stackoverflow.com/a/21049338/2810172

# built application files
*.apk
*.ap_

# files for the dex VM
*.dex

# Java class files
*.class

# built native files (uncomment if you build your own)
# *.o
# *.so

# generated files
bin/
gen/

# Ignore gradle files
.gradle/
build/

# Local configuration file (sdk path, etc)
local.properties

# Proguard folder generated by Eclipse
proguard/

# Eclipse Metadata
.metadata/

# Mac OS X clutter
*.DS_Store

# Windows clutter
Thumbs.db

# Intellij IDEA (see https://intellij-support.jetbrains.com/entries/23393067)
.idea/workspace.xml
.idea/tasks.xml
.idea/datasources.xml
.idea/dataSources.ids