Crash due to missing `other` for Russian on Gingerbread

Reported via ACRA by two users. This is at least the case for Russian but I haven't tried every language.

It seems that on Gingerbread (2.3.6 for the crash reports) you need to have the other string for plurals or else you get this:

android.content.res.Resources$NotFoundException: Plural resource ID #0x7f070000 quantity=10 item=other
at android.content.res.Resources.getQuantityText(Resources.java:225)
at android.content.res.Resources.getQuantityString(Resources.java:307)
at org.fdroid.fdroid.views.categories.CategoryController.onLoadFinished(CategoryController.java:182)
at org.fdroid.fdroid.views.categories.CategoryController.onLoadFinished(CategoryController.java:37)
at android.support.v4.app.LoaderManagerImpl$LoaderInfo.callOnLoadFinished(LoaderManager.java:476)
at android.support.v4.app.LoaderManagerImpl$LoaderInfo.onLoadComplete(LoaderManager.java:444)
at android.support.v4.content.Loader.deliverResult(Loader.java:126)
at android.support.v4.content.CursorLoader.deliverResult(CursorLoader.java:105)
at android.support.v4.content.CursorLoader.deliverResult(CursorLoader.java:37)
at android.support.v4.content.AsyncTaskLoader.dispatchOnLoadComplete(AsyncTaskLoader.java:252)
at android.support.v4.content.AsyncTaskLoader$LoadTask.onPostExecute(AsyncTaskLoader.java:80)
at android.support.v4.content.ModernAsyncTask.finish(ModernAsyncTask.java:485)
at android.support.v4.content.ModernAsyncTask$InternalHandler.handleMessage(ModernAsyncTask.java:502)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3687)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
at dalvik.system.NativeStart.main(Native Method)