for getting the list of variable names and for clearing all rule and
variable storage.
* compile.c - better error reporting for unknown rules; now it is a
hard error.
* hash.c/h - added hash_free to allow removal of elements from a hash
* rule.c/h - implemented rule freeing; stopped exporting rules to the
global module by default.
* variable.c - reclaim variable storage when disposing of variable
hash.
* build.jam - make grammar building work under NT
[SVN r18405]
* jam_src/builtins.c: New builtin SEARCH_FOR_TARGET.
* jam_src/rules.c
(bind_explicitly_located_targets): New function.
(search_for_target): New function.
* jam_src/make.c (make): Call 'bind_explicitly_located_targets()'
immediately on entering.
* jam_src/search.c (call_bind_rule): No longer 'static'.
* new/builtin.jam (c-scanner.process): Real implementation.
* test/dependency_test.py: Really test for dependencies.
[SVN r15646]
