Put proguard back in to avoid OutOfMemoryExceptions.

I removed it earlier because of warnings, but these weren't important.

app/build.gradle

@@ -43,8 +43,14 @@ android {
 
     buildTypes {
         debug {
+            runProguard true
+            proguardFile file("proguard-rules.pro")
             applicationIdSuffix ".debug"
         }
+        release {
+            runProguard true
+            proguardFile file("proguard-rules.pro")
+        }
     }
 
     // Avoid duplicate file errors during packaging.

app/proguard-rules.pro

@@ -0,0 +1,24 @@
+# Add project specific ProGuard rules here.
+# By default, the flags in this file are appended to flags specified
+# in /home/felix/software/android-studio/sdk/tools/proguard/proguard-android.txt
+# You can edit the include path and order by changing the proguardFiles
+# directive in build.gradle.
+#
+# For more details, see
+# http://developer.android.com/guide/developing/tools/proguard.html
+# Add any project specific keep options here:
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+# public *;
+#}
+-dontoptimize
+-dontobfuscate
+-dontpreverify
+-dontwarn scala.**
+-keep class !scala*.** { *; }
+-ignorewarnings
+
+# Suppress warnings caused by msgpack (code works fine anyway).
+-dontwarn