Addresses #1032

Fixes DEBUG=1 make, modified ignores.

git-svn-id: file:///svn/toku/tokudb.1032b@8160 c7de825b-a66e-492c-adef-691d508d4ae1

include/Makefile.include

@@ -41,7 +41,9 @@
 # To make warnings be warnngs instead of errors do
 #   make WERROR=
 
-DEBUG = 0
+ifeq ($(DEBUG),)
+    DEBUG = 0
+endif
 
 .DELETE_ON_ERROR: