cm: Build HexoLibre as part of common_full

Change-Id: I9af13beb525d118b48b5ca163760e14bd51c3a8a
diff --git a/config/common_full.mk b/config/common_full.mk
index 2c63a31..0312560 100644
--- a/config/common_full.mk
+++ b/config/common_full.mk
@@ -33,3 +33,7 @@
     vim \
     wget \
     zip
+
+# Themes
+PRODUCT_PACKAGES += \
+    HexoLibre