長いと怒られたので分割しました。gradleはこんなかんじです
release {
minifyEnabled true
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}

dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:22.0.0'
compile 'com.android.support:recyclerview-v7:22.+'
compile 'com.android.support:support-v4:22.+'
compile 'com.google.android.gms:play-services:7.8.0'
compile 'com.jakewharton:butterknife:6.1.0'
compile 'com.makeramen:roundedimageview:1.2.4'
// build.gradle
compile 'io.realm:realm-android:0.80.0'
compile 'com.squareup.retrofit:retrofit:1.9.0'
compile 'com.google.code.gson:gson:2.3.1'
compile 'io.reactivex:rxjava:1.0.8'
compile 'com.amazonaws:aws-android-sdk-core:2.1.9'
compile 'com.amazonaws:aws-android-sdk-s3:2.1.9'
compile 'com.squareup.picasso:picasso:2.5.2'
compile 'com.nostra13.universalimageloader:universal-image-loader:1.9.4'
compile 'com.loopj.android:android-async-http:1.4.8'
compile 'com.squareup.okhttp:okhttp:2.4.0'
}