Shave ~600KB off the apk size with the help of a FrankenDAO

We use a patched version of greenDAO's DaoGenerator with a bugfix
and additional support for
- composite primary keys
- WITHOUT_ROWID

We used to use jitpack for including our own greendao dependency into
Gadgetbridge. Since jitpack does not know how to build a real greenDAO
release, it will simply include all artifacts, including ftl templates
etc. which we do not need at runtime at all.

We could fix this by patching greenDAO build, but we actually don't need
to do that, since we can simply use the pristine greenDAO runtime
dependency. It will happily use our custom DAOGenerator-generated
entities.

app/build.gradle

@@ -75,7 +75,9 @@ dependencies {
     compile 'com.github.pfichtner:durationformatter:0.1.1'
     compile 'de.cketti.library.changelog:ckchangelog:1.2.2'
     compile 'net.e175.klaus:solarpositioning:0.0.9'
-    compile 'com.github.freeyourgadget:greendao:1998d7cd2d21f662c6044f6ccf3b3a251bbad341'
+    // use pristine greendao instead of our custom version, since our custom jitpack-packaged
+    // version contains way too much and our custom patches are in the generator only.
+    compile 'org.greenrobot:greendao:2.2.1'
     compile 'org.apache.commons:commons-lang3:3.5'
 
 //    compile project(":DaoCore")