Resolves: #i124896# [API CHANGE] remove obsoleted rtl/allocator.hxx

remove obsoleted sal-module-internal custom STL allocator

The SAL module avoided the heavy dependency on the stlport4-libraries by using
a custom allocator for its internal STL containers. With stlport4 removed these
dependencies are gone and the SAL-internal custom allocator is obsoleted.

(cherry picked from commit c6e0325df6efce45dbb2616a32b7745c449c6c58)

Conflicts:
	include/osl/diagnose.hxx
	include/rtl/allocator.hxx
	sal/osl/w32/procimpl.cxx
	sal/qa/osl/process/osl_process.cxx
	sal/rtl/bootstrap.cxx
	sal/rtl/source/hash.cxx
	sal/rtl/source/unload.cxx

Change-Id: I8515382828eda36aba1fec5f23e0f2a89aef7a33
Related: #i124896# remove obsoleted pq_allocator.hxx

Change-Id: I8a2b54c97f20e581b9703bf33dbba537c2f603c2