* configure.ac: Define automake conditinal ENABLE_TLH if SSA enabled.

* configure.ac: Define automake conditinal ENABLE_TLH if SSA enabled.
* src/mm/Makefile.am [ENABLE_TLH]: Build tlh.c
* src/mm/tlh.c,
src/mm/tlh.h: New files: thread local heap implementation.
* src/threads/posix/thread-posix.c,
src/threads/posix/thread-posix.h (threadobject_t) [ENABLE_TLH]: added a tlh_t memeber, (threads_impl_thread_init) [ENABLE_TLH]: calling tlh_init, (threads_impl_thread_reuse) [ENABLE_TLH]: calling tlh_init and tlh_destroy.
* src/vm/jit/optimizing/escape.c: Removed now obsolete code.