Allow sites to overrid CONFIG_SITE through CONFIG_SITE.local

Author: klemenv

configure/CONFIG_SITE

@@ -2,7 +2,7 @@
 
 # Set this if you intend to build with a specific python version
 #   e.g. using python3
-# PYTHON_CONFIG=python3-config
+PYTHON_CONFIG=python3-config
 
 # Make any application-specific changes to the EPICS build
 #   configuration variables in this file.
@@ -35,3 +35,6 @@ CHECK_RELEASE = YES
 # You must rebuild in the iocBoot directory for this to
 #   take effect.
 #IOCS_APPL_TOP = </IOC/path/to/application/top>
+
+# Allow site specific changes that are not part of this repo
+-include $(TOP)/configure/RELEASE.local