Drop mod_java from jessie build

Right now mod_java fails to build on sid and jessie.  We have a
possible solution, but we'll just disable the build of the module
while we test and verify.

debian/bootstrap.sh

@@ -39,6 +39,7 @@ avoid_mods_sid=(
 )
 avoid_mods_jessie=(
   directories/mod_ldap
+  languages/mod_java
 )
 avoid_mods_wheezy=(
 )