Python: Automatically conform to PEP440 for version numbers. ported from Unicorn Python binding
diff --git a/pkgconfig.mk b/pkgconfig.mk
index b6742b6..7ff49ac 100644
--- a/pkgconfig.mk
+++ b/pkgconfig.mk
@@ -7,3 +7,6 @@
 
 # version bugfix level. Example: PKG_EXTRA = 1
 PKG_EXTRA = 5
+
+# version tag. Examples: rc1, b2, post1
+PKG_TAG = rc2