Added A Roll Modifier Picker

Currently the roll modifier is from -5 to + 50. This can be updated via
values/mod.xml
Change-Id: I32c5d7ed1c67e0d8bc1b1434025d14134f8bc583
Signed-off-by: Ricky Barrette <rickbarrette@gmail.com>

ExaltedDice/res/layout/main.xml

@@ -15,7 +15,7 @@
         <RelativeLayout
             android:layout_width="0px"
             android:layout_height="wrap_content"
-            android:layout_weight="1" >
+            android:layout_weight="2" >
 
             <include
                 android:id="@+id/die_selector"