Refactor to support more varied testing.

Refactor the test harness to support three types of tests:
- unit: White box unit tests.  These tests have full access to all
  internal jemalloc library symbols.  Though in actuality all symbols
  are prefixed by jet_, macro-based name mangling abstracts this away
  from test code.
- integration: Black box integration tests.  These tests link with
  the installable shared jemalloc library, and with the exception of
  some utility code and configure-generated macro definitions, they have
  no access to jemalloc internals.
- stress: Black box stress tests.  These tests link with the installable
  shared jemalloc library, as well as with an internal allocator with
  symbols prefixed by jet_ (same as for unit tests) that can be used to
  allocate data structures that are internal to the test code.

Move existing tests into test/{unit,integration}/ as appropriate.

Split out internal parts of jemalloc_defs.h.in and put them in
jemalloc_internal_defs.h.in.  This reduces internals exposure to
applications that #include <jemalloc/jemalloc.h>.

Refactor jemalloc.h header generation so that a single header file
results, and the prototypes can be used to generate jet_ prototypes for
tests.  Split jemalloc.h.in into multiple parts (jemalloc_defs.h.in,
jemalloc_macros.h.in, jemalloc_protos.h.in, jemalloc_mangle.h.in) and
use a shell script to generate a unified jemalloc.h at configure time.

Change the default private namespace prefix from "" to "je_".

Add missing private namespace mangling.

Remove hard-coded private_namespace.h.  Instead generate it and
private_unnamespace.h from private_symbols.txt.  Use similar logic for
public symbols, which aids in name mangling for jet_ symbols.

Add test_warn() and test_fail().  Replace existing exit(1) calls with
test_fail() calls.

.gitignore

@@ -1,25 +1,56 @@
 /autom4te.cache/
+
+/bin/jemalloc.sh
+
 /config.stamp
 /config.log
 /config.status
 /configure
+
 /doc/html.xsl
 /doc/manpages.xsl
 /doc/jemalloc.xml
 /doc/jemalloc.html
 /doc/jemalloc.3
+
 /lib/
+
 /Makefile
-/include/jemalloc/internal/jemalloc_internal\.h
-/include/jemalloc/internal/size_classes\.h
-/include/jemalloc/jemalloc\.h
-/include/jemalloc/jemalloc_defs\.h
-/test/jemalloc_test\.h
+
+/include/jemalloc/internal/jemalloc_internal.h
+/include/jemalloc/internal/jemalloc_internal_defs.h
+/include/jemalloc/internal/private_namespace.h
+/include/jemalloc/internal/private_unnamespace.h
+/include/jemalloc/internal/public_namespace.h
+/include/jemalloc/internal/public_unnamespace.h
+/include/jemalloc/internal/size_classes.h
+/include/jemalloc/jemalloc.h
+/include/jemalloc/jemalloc_defs.h
+/include/jemalloc/jemalloc_macros.h
+/include/jemalloc/jemalloc_protos.h
+/include/jemalloc/jemalloc_protos_jet.h
+/include/jemalloc/jemalloc_mangle.h
+
 /src/*.[od]
-/test/*.[od]
-/test/*.out
-/test/[a-zA-Z_]*
-!test/*.c
-!test/*.exp
+
+/test/test.sh
+test/include/test/jemalloc_test.h
+
+/test/integration/[A-Za-z]*
+!/test/integration/*.*
+/test/integration/*.[od]
+/test/integration/*.out
+
+/test/src/*.[od]
+
+/test/stress/[A-Za-z]*
+!/test/stress/*.*
+/test/stress/*.[od]
+/test/stress/*.out
+
+/test/unit/[A-Za-z]*
+!/test/unit/*.*
+/test/unit/*.[od]
+/test/unit/*.out
+
 /VERSION
-/bin/jemalloc.sh