Add callback groups

Allow named collections of callbacks to be defined and used anywhere
callbacks are used.

Change-Id: I3224aa06b2250e9a055bc70d20c186caecd033af
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/src/Makefile.am b/src/Makefile.am
index f223713..c77c0a8 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -22,6 +22,7 @@
 CLEANFILES = generated.hpp
 
 TEMPLATES = \
+	templates/callbackgroup.mako.cpp \
 	templates/generated.mako.hpp \
 	templates/journal.mako.cpp